Atmospheric Carbon Dioxide

Atmospheric carbon dioxide at Mauna Loa since 1958 and the global mean since 1979: monthly and yearly levels, the yearly increase and the seasonal cycle. Latest month, September 2026: 426.07 ppm.

Data as of 2026-11-12. Last revised 12 November 2026 (2026-11-12).

Key Facts

The Mauna Loa monthly mean for September 2026 was 426.07 ppm, up 24.84 ppm from 401.23 ppm in September 2016.
The week starting 1 November 2026 averaged 428.57 ppm at Mauna Loa, 3.36 ppm above the same week a year earlier. Recent weeks are preliminary.
The Mauna Loa annual mean was 427.35 ppm in 2025, 2.74 ppm more than in 2024.
The first full year of the Mauna Loa record, 1959, averaged 315.98 ppm. The 2025 mean is 111.37 ppm (35 percent) higher.
The yearly increase at Mauna Loa averaged 0.86 ppm a year in the 1960s and 2.40 ppm a year in the 2010s.
Each year the Mauna Loa level peaks in May, about 3.4 ppm above its trend, and is lowest in September, about 3.5 ppm below it (average of 2017 to 2026).
The global marine surface mean was 425.62 ppm in 2025, 1.73 ppm below the Mauna Loa value for the same year.

What the Numbers Are

Levels are the mole fraction of carbon dioxide in dry air, in parts per million (ppm): micromoles of CO2 per mole of air. The Mauna Loa series is measured at a mountain observatory in Hawaii, about 3,400 metres above sea level and far from local sources. It began in March 1958 with Charles David Keeling at the Scripps Institution of Oceanography, and NOAA has run it since 1974. The global series averages marine surface sites from NOAA's air sampling network around the world and starts in 1979.

The monthly mean follows a yearly cycle, as plants in the northern hemisphere take up CO2 in summer and release it in winter. The trend line removes that cycle. In the early years some months are missing and NOAA filled them by interpolation: 196 of the 823 Mauna Loa months are marked that way in the data download. Measurements at Mauna Loa were suspended on 29 November 2022 because of the volcano's eruption and resumed in July 2023. Values from December 2022 to 4 July 2023 are from a site at the Maunakea Observatories, about 21 miles to the north. The latest year and the latest weeks are preliminary and can change a little when NOAA recalibrates.

This page reports measured levels. It does not model emissions or temperature, and it makes no claim about how much of the change in any station's temperature the rise in CO2 explains.

Monthly Levels since 1958

1958-03 to 2026-09

Monthly mean CO2 at Mauna Loa from 1958-03 to 2026-09, its trend with the seasonal cycle removed, and the global marine surface mean from 1979.

Monthly carbon dioxide at Mauna Loa and the global mean, in ppm
Month	Mauna Loa monthly	Mauna Loa trend	Global mean
1958-03	315.71 ppm	314.44 ppm	n/a
1958-04	317.45 ppm	315.16 ppm	n/a
1958-05	317.51 ppm	314.69 ppm	n/a
1958-06	317.27 ppm	315.15 ppm	n/a
1958-07	315.87 ppm	315.20 ppm	n/a
1958-08	314.93 ppm	316.21 ppm	n/a
1958-09	313.21 ppm	316.11 ppm	n/a
1958-10	312.42 ppm	315.41 ppm	n/a
1958-11	313.33 ppm	315.21 ppm	n/a
1958-12	314.67 ppm	315.43 ppm	n/a
1959-01	315.58 ppm	315.52 ppm	n/a
1959-02	316.49 ppm	315.84 ppm	n/a
1959-03	316.65 ppm	315.37 ppm	n/a
1959-04	317.72 ppm	315.42 ppm	n/a
1959-05	318.29 ppm	315.46 ppm	n/a
1959-06	318.15 ppm	316.00 ppm	n/a
1959-07	316.54 ppm	315.87 ppm	n/a
1959-08	314.80 ppm	316.09 ppm	n/a
1959-09	313.84 ppm	316.75 ppm	n/a
1959-10	313.33 ppm	316.34 ppm	n/a
1959-11	314.81 ppm	316.69 ppm	n/a
1959-12	315.58 ppm	316.35 ppm	n/a
1960-01	316.43 ppm	316.38 ppm	n/a
1960-02	316.98 ppm	316.33 ppm	n/a
1960-03	317.58 ppm	316.27 ppm	n/a
1960-04	319.03 ppm	316.70 ppm	n/a
1960-05	320.03 ppm	317.19 ppm	n/a
1960-06	319.58 ppm	317.45 ppm	n/a
1960-07	318.18 ppm	317.54 ppm	n/a
1960-08	315.90 ppm	317.22 ppm	n/a
1960-09	314.17 ppm	317.10 ppm	n/a
1960-10	313.83 ppm	316.85 ppm	n/a
1960-11	315.00 ppm	316.89 ppm	n/a
1960-12	316.19 ppm	316.96 ppm	n/a
1961-01	316.89 ppm	316.84 ppm	n/a
1961-02	317.70 ppm	317.05 ppm	n/a
1961-03	318.54 ppm	317.25 ppm	n/a
1961-04	319.48 ppm	317.16 ppm	n/a
1961-05	320.58 ppm	317.73 ppm	n/a
1961-06	319.77 ppm	317.61 ppm	n/a
1961-07	318.56 ppm	317.89 ppm	n/a
1961-08	316.79 ppm	318.09 ppm	n/a
1961-09	314.99 ppm	317.92 ppm	n/a
1961-10	315.31 ppm	318.34 ppm	n/a
1961-11	316.10 ppm	318.00 ppm	n/a
1961-12	317.01 ppm	317.78 ppm	n/a
1962-01	317.94 ppm	317.89 ppm	n/a
1962-02	318.55 ppm	317.89 ppm	n/a
1962-03	319.68 ppm	318.39 ppm	n/a
1962-04	320.57 ppm	318.24 ppm	n/a
1962-05	321.02 ppm	318.16 ppm	n/a
1962-06	320.62 ppm	318.45 ppm	n/a
1962-07	319.61 ppm	318.94 ppm	n/a
1962-08	317.40 ppm	318.71 ppm	n/a
1962-09	316.24 ppm	319.18 ppm	n/a
1962-10	315.42 ppm	318.46 ppm	n/a
1962-11	316.69 ppm	318.59 ppm	n/a
1962-12	317.70 ppm	318.47 ppm	n/a
1963-01	318.74 ppm	318.69 ppm	n/a
1963-02	319.07 ppm	318.41 ppm	n/a
1963-03	319.86 ppm	318.57 ppm	n/a
1963-04	321.38 ppm	319.05 ppm	n/a
1963-05	322.24 ppm	319.38 ppm	n/a
1963-06	321.49 ppm	319.31 ppm	n/a
1963-07	319.74 ppm	319.07 ppm	n/a
1963-08	317.77 ppm	319.07 ppm	n/a
1963-09	316.21 ppm	319.16 ppm	n/a
1963-10	315.99 ppm	319.03 ppm	n/a
1963-11	317.07 ppm	318.98 ppm	n/a
1963-12	318.35 ppm	319.13 ppm	n/a
1964-01	319.57 ppm	319.52 ppm	n/a
1964-02	320.04 ppm	319.37 ppm	n/a
1964-03	320.75 ppm	319.41 ppm	n/a
1964-04	321.84 ppm	319.46 ppm	n/a
1964-05	322.25 ppm	319.37 ppm	n/a
1964-06	321.89 ppm	319.73 ppm	n/a
1964-07	320.44 ppm	319.79 ppm	n/a
1964-08	318.69 ppm	320.03 ppm	n/a
1964-09	316.71 ppm	319.67 ppm	n/a
1964-10	316.87 ppm	319.93 ppm	n/a
1964-11	317.68 ppm	319.59 ppm	n/a
1964-12	318.71 ppm	319.49 ppm	n/a
1965-01	319.44 ppm	319.38 ppm	n/a
1965-02	320.44 ppm	319.79 ppm	n/a
1965-03	320.89 ppm	319.59 ppm	n/a
1965-04	322.14 ppm	319.79 ppm	n/a
1965-05	322.17 ppm	319.28 ppm	n/a
1965-06	321.87 ppm	319.68 ppm	n/a
1965-07	321.21 ppm	320.53 ppm	n/a
1965-08	318.87 ppm	320.18 ppm	n/a
1965-09	317.82 ppm	320.78 ppm	n/a
1965-10	317.30 ppm	320.37 ppm	n/a
1965-11	318.87 ppm	320.79 ppm	n/a
1965-12	319.42 ppm	320.20 ppm	n/a
1966-01	320.62 ppm	320.57 ppm	n/a
1966-02	321.60 ppm	320.94 ppm	n/a
1966-03	322.39 ppm	321.08 ppm	n/a
1966-04	323.70 ppm	321.34 ppm	n/a
1966-05	324.08 ppm	321.18 ppm	n/a
1966-06	323.75 ppm	321.55 ppm	n/a
1966-07	322.37 ppm	321.69 ppm	n/a
1966-08	320.36 ppm	321.68 ppm	n/a
1966-09	318.64 ppm	321.61 ppm	n/a
1966-10	318.10 ppm	321.18 ppm	n/a
1966-11	319.78 ppm	321.71 ppm	n/a
1966-12	321.02 ppm	321.81 ppm	n/a
1967-01	322.33 ppm	322.28 ppm	n/a
1967-02	322.50 ppm	321.83 ppm	n/a
1967-03	323.03 ppm	321.72 ppm	n/a
1967-04	324.41 ppm	322.05 ppm	n/a
1967-05	325.00 ppm	322.09 ppm	n/a
1967-06	324.09 ppm	321.89 ppm	n/a
1967-07	322.54 ppm	321.86 ppm	n/a
1967-08	320.92 ppm	322.24 ppm	n/a
1967-09	319.25 ppm	322.24 ppm	n/a
1967-10	319.39 ppm	322.48 ppm	n/a
1967-11	320.73 ppm	322.66 ppm	n/a
1967-12	321.96 ppm	322.74 ppm	n/a
1968-01	322.57 ppm	322.51 ppm	n/a
1968-02	323.15 ppm	322.48 ppm	n/a
1968-03	323.89 ppm	322.55 ppm	n/a
1968-04	325.02 ppm	322.63 ppm	n/a
1968-05	325.57 ppm	322.66 ppm	n/a
1968-06	325.36 ppm	323.17 ppm	n/a
1968-07	324.14 ppm	323.48 ppm	n/a
1968-08	322.11 ppm	323.46 ppm	n/a
1968-09	320.33 ppm	323.33 ppm	n/a
1968-10	320.25 ppm	323.34 ppm	n/a
1968-11	321.32 ppm	323.26 ppm	n/a
1968-12	322.89 ppm	323.68 ppm	n/a
1969-01	324.00 ppm	323.95 ppm	n/a
1969-02	324.41 ppm	323.75 ppm	n/a
1969-03	325.63 ppm	324.31 ppm	n/a
1969-04	326.66 ppm	324.28 ppm	n/a
1969-05	327.38 ppm	324.46 ppm	n/a
1969-06	326.71 ppm	324.49 ppm	n/a
1969-07	325.88 ppm	325.19 ppm	n/a
1969-08	323.66 ppm	324.99 ppm	n/a
1969-09	322.38 ppm	325.38 ppm	n/a
1969-10	321.78 ppm	324.89 ppm	n/a
1969-11	322.85 ppm	324.80 ppm	n/a
1969-12	324.11 ppm	324.91 ppm	n/a
1970-01	325.06 ppm	325.01 ppm	n/a
1970-02	325.99 ppm	325.31 ppm	n/a
1970-03	326.93 ppm	325.61 ppm	n/a
1970-04	328.13 ppm	325.75 ppm	n/a
1970-05	328.08 ppm	325.15 ppm	n/a
1970-06	327.67 ppm	325.44 ppm	n/a
1970-07	326.34 ppm	325.65 ppm	n/a
1970-08	324.68 ppm	326.02 ppm	n/a
1970-09	323.10 ppm	326.11 ppm	n/a
1970-10	323.06 ppm	326.18 ppm	n/a
1970-11	324.01 ppm	325.96 ppm	n/a
1970-12	325.13 ppm	325.93 ppm	n/a
1971-01	326.17 ppm	326.12 ppm	n/a
1971-02	326.69 ppm	326.01 ppm	n/a
1971-03	327.18 ppm	325.85 ppm	n/a
1971-04	327.78 ppm	325.39 ppm	n/a
1971-05	328.93 ppm	325.99 ppm	n/a
1971-06	328.57 ppm	326.34 ppm	n/a
1971-07	327.36 ppm	326.67 ppm	n/a
1971-08	325.43 ppm	326.77 ppm	n/a
1971-09	323.36 ppm	326.38 ppm	n/a
1971-10	323.56 ppm	326.69 ppm	n/a
1971-11	324.80 ppm	326.75 ppm	n/a
1971-12	326.01 ppm	326.81 ppm	n/a
1972-01	326.77 ppm	326.71 ppm	n/a
1972-02	327.63 ppm	326.96 ppm	n/a
1972-03	327.75 ppm	326.39 ppm	n/a
1972-04	329.72 ppm	327.30 ppm	n/a
1972-05	330.07 ppm	327.12 ppm	n/a
1972-06	329.09 ppm	326.87 ppm	n/a
1972-07	328.04 ppm	327.38 ppm	n/a
1972-08	326.32 ppm	327.69 ppm	n/a
1972-09	324.84 ppm	327.88 ppm	n/a
1972-10	325.20 ppm	328.33 ppm	n/a
1972-11	326.50 ppm	328.46 ppm	n/a
1972-12	327.55 ppm	328.35 ppm	n/a
1973-01	328.55 ppm	328.49 ppm	n/a
1973-02	329.57 ppm	328.89 ppm	n/a
1973-03	330.30 ppm	328.97 ppm	n/a
1973-04	331.50 ppm	329.10 ppm	n/a
1973-05	332.48 ppm	329.52 ppm	n/a
1973-06	332.07 ppm	329.83 ppm	n/a
1973-07	330.87 ppm	330.18 ppm	n/a
1973-08	329.31 ppm	330.66 ppm	n/a
1973-09	327.52 ppm	330.56 ppm	n/a
1973-10	327.19 ppm	330.33 ppm	n/a
1973-11	328.17 ppm	330.13 ppm	n/a
1973-12	328.65 ppm	329.45 ppm	n/a
1974-01	329.36 ppm	329.30 ppm	n/a
1974-02	330.71 ppm	330.03 ppm	n/a
1974-03	331.49 ppm	330.15 ppm	n/a
1974-04	332.65 ppm	330.24 ppm	n/a
1974-05	333.19 ppm	330.22 ppm	n/a
1974-06	332.20 ppm	329.79 ppm	n/a
1974-07	331.07 ppm	330.21 ppm	n/a
1974-08	329.15 ppm	330.54 ppm	n/a
1974-09	327.33 ppm	330.44 ppm	n/a
1974-10	327.28 ppm	330.53 ppm	n/a
1974-11	328.31 ppm	330.50 ppm	n/a
1974-12	329.58 ppm	330.55 ppm	n/a
1975-01	330.73 ppm	330.84 ppm	n/a
1975-02	331.46 ppm	330.85 ppm	n/a
1975-03	331.94 ppm	330.37 ppm	n/a
1975-04	333.11 ppm	330.53 ppm	n/a
1975-05	333.95 ppm	330.98 ppm	n/a
1975-06	333.42 ppm	331.01 ppm	n/a
1975-07	331.97 ppm	331.12 ppm	n/a
1975-08	329.95 ppm	331.33 ppm	n/a
1975-09	328.49 ppm	331.60 ppm	n/a
1975-10	328.36 ppm	331.61 ppm	n/a
1975-11	329.38 ppm	331.57 ppm	n/a
1975-12	330.77 ppm	331.73 ppm	n/a
1976-01	331.56 ppm	331.67 ppm	n/a
1976-02	332.74 ppm	332.14 ppm	n/a
1976-03	333.36 ppm	331.79 ppm	n/a
1976-04	334.74 ppm	332.16 ppm	n/a
1976-05	334.72 ppm	331.75 ppm	n/a
1976-06	333.97 ppm	331.56 ppm	n/a
1976-07	333.08 ppm	332.23 ppm	n/a
1976-08	330.68 ppm	332.07 ppm	n/a
1976-09	328.96 ppm	332.07 ppm	n/a
1976-10	328.72 ppm	331.98 ppm	n/a
1976-11	330.16 ppm	332.35 ppm	n/a
1976-12	331.62 ppm	332.59 ppm	n/a
1977-01	332.68 ppm	332.77 ppm	n/a
1977-02	333.17 ppm	332.58 ppm	n/a
1977-03	334.96 ppm	333.40 ppm	n/a
1977-04	336.14 ppm	333.54 ppm	n/a
1977-05	336.93 ppm	334.00 ppm	n/a
1977-06	336.17 ppm	333.79 ppm	n/a
1977-07	334.89 ppm	334.01 ppm	n/a
1977-08	332.56 ppm	333.91 ppm	n/a
1977-09	331.29 ppm	334.36 ppm	n/a
1977-10	331.28 ppm	334.51 ppm	n/a
1977-11	332.46 ppm	334.68 ppm	n/a
1977-12	333.60 ppm	334.58 ppm	n/a
1978-01	334.94 ppm	335.01 ppm	n/a
1978-02	335.26 ppm	334.60 ppm	n/a
1978-03	336.66 ppm	335.00 ppm	n/a
1978-04	337.69 ppm	335.07 ppm	n/a
1978-05	338.02 ppm	335.08 ppm	n/a
1978-06	338.01 ppm	335.60 ppm	n/a
1978-07	336.50 ppm	335.65 ppm	n/a
1978-08	334.42 ppm	335.87 ppm	n/a
1978-09	332.36 ppm	335.51 ppm	n/a
1978-10	332.45 ppm	335.72 ppm	n/a
1978-11	333.76 ppm	335.99 ppm	n/a
1978-12	334.91 ppm	335.87 ppm	n/a
1979-01	336.14 ppm	336.22 ppm	336.56 ppm
1979-02	336.69 ppm	336.00 ppm	337.29 ppm
1979-03	338.27 ppm	336.56 ppm	337.88 ppm
1979-04	338.82 ppm	336.11 ppm	338.32 ppm
1979-05	339.24 ppm	336.24 ppm	338.26 ppm
1979-06	339.26 ppm	336.83 ppm	337.38 ppm
1979-07	337.54 ppm	336.69 ppm	335.56 ppm
1979-08	335.72 ppm	337.20 ppm	334.36 ppm
1979-09	333.97 ppm	337.19 ppm	335.02 ppm
1979-10	334.24 ppm	337.57 ppm	336.36 ppm
1979-11	335.32 ppm	337.59 ppm	337.36 ppm
1979-12	336.81 ppm	337.83 ppm	337.89 ppm
1980-01	337.90 ppm	338.13 ppm	338.58 ppm
1980-02	338.34 ppm	337.85 ppm	339.26 ppm
1980-03	340.07 ppm	338.51 ppm	339.60 ppm
1980-04	340.93 ppm	338.31 ppm	340.00 ppm
1980-05	341.45 ppm	338.40 ppm	340.44 ppm
1980-06	341.36 ppm	338.85 ppm	339.99 ppm
1980-07	339.45 ppm	338.56 ppm	338.44 ppm
1980-08	337.67 ppm	339.07 ppm	337.22 ppm
1980-09	336.25 ppm	339.38 ppm	337.05 ppm
1980-10	336.14 ppm	339.40 ppm	337.82 ppm
1980-11	337.30 ppm	339.46 ppm	338.93 ppm
1980-12	338.29 ppm	339.26 ppm	339.63 ppm
1981-01	339.29 ppm	339.42 ppm	340.18 ppm
1981-02	340.55 ppm	339.98 ppm	340.75 ppm
1981-03	341.63 ppm	340.08 ppm	341.38 ppm
1981-04	342.60 ppm	339.98 ppm	341.68 ppm
1981-05	343.04 ppm	339.97 ppm	341.43 ppm
1981-06	342.54 ppm	340.06 ppm	340.63 ppm
1981-07	340.82 ppm	339.92 ppm	339.23 ppm
1981-08	338.48 ppm	339.87 ppm	338.08 ppm
1981-09	336.95 ppm	340.17 ppm	337.97 ppm
1981-10	337.05 ppm	340.39 ppm	339.07 ppm
1981-11	338.58 ppm	340.75 ppm	340.17 ppm
1981-12	339.91 ppm	340.85 ppm	340.74 ppm
1982-01	340.93 ppm	341.09 ppm	341.36 ppm
1982-02	341.76 ppm	341.16 ppm	341.95 ppm
1982-03	342.78 ppm	341.18 ppm	342.23 ppm
1982-04	343.96 ppm	341.32 ppm	342.52 ppm
1982-05	344.77 ppm	341.67 ppm	342.37 ppm
1982-06	343.88 ppm	341.43 ppm	341.49 ppm
1982-07	342.42 ppm	341.61 ppm	339.75 ppm
1982-08	340.24 ppm	341.64 ppm	338.11 ppm
1982-09	338.37 ppm	341.56 ppm	338.16 ppm
1982-10	338.41 ppm	341.77 ppm	339.61 ppm
1982-11	339.44 ppm	341.59 ppm	340.95 ppm
1982-12	340.78 ppm	341.71 ppm	341.77 ppm
1983-01	341.57 ppm	341.75 ppm	342.37 ppm
1983-02	342.78 ppm	342.25 ppm	342.74 ppm
1983-03	343.37 ppm	341.85 ppm	343.04 ppm
1983-04	345.40 ppm	342.76 ppm	343.51 ppm
1983-05	346.14 ppm	342.97 ppm	343.84 ppm
1983-06	345.76 ppm	343.30 ppm	343.50 ppm
1983-07	344.32 ppm	343.56 ppm	342.14 ppm
1983-08	342.51 ppm	343.89 ppm	340.62 ppm
1983-09	340.46 ppm	343.59 ppm	340.53 ppm
1983-10	340.53 ppm	343.86 ppm	341.75 ppm
1983-11	341.79 ppm	343.92 ppm	342.83 ppm
1983-12	343.20 ppm	344.12 ppm	343.49 ppm
1984-01	344.21 ppm	344.32 ppm	344.32 ppm
1984-02	344.92 ppm	344.39 ppm	344.82 ppm
1984-03	345.68 ppm	344.26 ppm	344.96 ppm
1984-04	347.37 ppm	344.75 ppm	345.19 ppm
1984-05	347.77 ppm	344.59 ppm	345.33 ppm
1984-06	347.16 ppm	344.73 ppm	344.57 ppm
1984-07	345.79 ppm	345.02 ppm	343.20 ppm
1984-08	343.74 ppm	345.12 ppm	342.21 ppm
1984-09	341.59 ppm	344.76 ppm	342.13 ppm
1984-10	341.86 ppm	345.19 ppm	342.99 ppm
1984-11	343.31 ppm	345.41 ppm	344.16 ppm
1984-12	345.00 ppm	345.88 ppm	345.00 ppm
1985-01	345.48 ppm	345.59 ppm	345.35 ppm
1985-02	346.41 ppm	345.92 ppm	345.80 ppm
1985-03	347.91 ppm	346.56 ppm	346.64 ppm
1985-04	348.66 ppm	346.08 ppm	346.94 ppm
1985-05	349.28 ppm	346.12 ppm	346.78 ppm
1985-06	348.65 ppm	346.23 ppm	346.26 ppm
1985-07	346.90 ppm	346.08 ppm	344.92 ppm
1985-08	345.26 ppm	346.57 ppm	343.41 ppm
1985-09	343.47 ppm	346.59 ppm	343.37 ppm
1985-10	343.35 ppm	346.60 ppm	344.64 ppm
1985-11	344.73 ppm	346.82 ppm	345.79 ppm
1985-12	346.12 ppm	347.04 ppm	346.55 ppm
1986-01	346.78 ppm	346.82 ppm	347.11 ppm
1986-02	347.48 ppm	346.98 ppm	347.34 ppm
1986-03	348.25 ppm	346.93 ppm	347.71 ppm
1986-04	349.86 ppm	347.29 ppm	348.22 ppm
1986-05	350.52 ppm	347.42 ppm	348.32 ppm
1986-06	349.98 ppm	347.61 ppm	347.76 ppm
1986-07	348.25 ppm	347.43 ppm	346.29 ppm
1986-08	346.17 ppm	347.51 ppm	344.92 ppm
1986-09	345.48 ppm	348.61 ppm	344.86 ppm
1986-10	344.82 ppm	348.04 ppm	346.03 ppm
1986-11	346.22 ppm	348.28 ppm	347.30 ppm
1986-12	347.48 ppm	348.36 ppm	347.76 ppm
1987-01	348.73 ppm	348.66 ppm	348.01 ppm
1987-02	348.92 ppm	348.24 ppm	348.56 ppm
1987-03	349.81 ppm	348.39 ppm	349.28 ppm
1987-04	351.40 ppm	348.84 ppm	349.98 ppm
1987-05	352.15 ppm	349.09 ppm	350.26 ppm
1987-06	351.58 ppm	349.29 ppm	349.46 ppm
1987-07	350.21 ppm	349.51 ppm	347.84 ppm
1987-08	348.20 ppm	349.65 ppm	346.61 ppm
1987-09	346.66 ppm	349.85 ppm	346.70 ppm
1987-10	346.72 ppm	349.96 ppm	347.97 ppm
1987-11	348.08 ppm	350.15 ppm	349.25 ppm
1987-12	349.28 ppm	350.14 ppm	350.21 ppm
1988-01	350.51 ppm	350.49 ppm	350.91 ppm
1988-02	351.70 ppm	350.99 ppm	351.47 ppm
1988-03	352.50 ppm	350.99 ppm	351.85 ppm
1988-04	353.67 ppm	351.03 ppm	352.29 ppm
1988-05	354.35 ppm	351.22 ppm	352.46 ppm
1988-06	353.88 ppm	351.55 ppm	351.76 ppm
1988-07	352.80 ppm	352.16 ppm	350.28 ppm
1988-08	350.49 ppm	352.01 ppm	349.10 ppm
1988-09	348.97 ppm	352.18 ppm	349.27 ppm
1988-10	349.37 ppm	352.62 ppm	350.44 ppm
1988-11	350.42 ppm	352.53 ppm	351.61 ppm
1988-12	351.62 ppm	352.52 ppm	352.46 ppm
1989-01	353.07 ppm	352.99 ppm	353.01 ppm
1989-02	353.43 ppm	352.69 ppm	353.46 ppm
1989-03	354.08 ppm	352.60 ppm	354.01 ppm
1989-04	355.72 ppm	353.07 ppm	354.38 ppm
1989-05	355.95 ppm	352.78 ppm	354.19 ppm
1989-06	355.44 ppm	353.06 ppm	353.26 ppm
1989-07	354.05 ppm	353.38 ppm	351.56 ppm
1989-08	351.84 ppm	353.43 ppm	350.21 ppm
1989-09	350.09 ppm	353.37 ppm	350.56 ppm
1989-10	350.33 ppm	353.57 ppm	351.85 ppm
1989-11	351.55 ppm	353.68 ppm	353.04 ppm
1989-12	352.91 ppm	353.84 ppm	353.91 ppm
1990-01	353.86 ppm	353.78 ppm	354.48 ppm
1990-02	355.10 ppm	354.37 ppm	354.88 ppm
1990-03	355.75 ppm	354.27 ppm	355.20 ppm
1990-04	356.38 ppm	353.76 ppm	355.51 ppm
1990-05	357.38 ppm	354.23 ppm	355.41 ppm
1990-06	356.39 ppm	354.02 ppm	354.32 ppm
1990-07	354.89 ppm	354.24 ppm	352.70 ppm
1990-08	353.06 ppm	354.68 ppm	351.58 ppm
1990-09	351.38 ppm	354.69 ppm	351.79 ppm
1990-10	351.69 ppm	354.94 ppm	353.19 ppm
1990-11	353.14 ppm	355.18 ppm	354.45 ppm
1990-12	354.41 ppm	355.26 ppm	355.19 ppm
1991-01	354.93 ppm	354.91 ppm	355.76 ppm
1991-02	355.82 ppm	355.11 ppm	356.19 ppm
1991-03	357.33 ppm	355.79 ppm	356.69 ppm
1991-04	358.77 ppm	356.13 ppm	357.19 ppm
1991-05	359.23 ppm	356.10 ppm	357.11 ppm
1991-06	358.23 ppm	355.88 ppm	356.18 ppm
1991-07	356.30 ppm	355.69 ppm	354.53 ppm
1991-08	353.97 ppm	355.59 ppm	353.06 ppm
1991-09	352.34 ppm	355.66 ppm	352.93 ppm
1991-10	352.43 ppm	355.69 ppm	354.01 ppm
1991-11	353.89 ppm	355.87 ppm	355.16 ppm
1991-12	355.21 ppm	356.02 ppm	355.95 ppm
1992-01	356.34 ppm	356.29 ppm	356.54 ppm
1992-02	357.21 ppm	356.47 ppm	356.89 ppm
1992-03	357.97 ppm	356.38 ppm	357.26 ppm
1992-04	359.22 ppm	356.51 ppm	357.76 ppm
1992-05	359.71 ppm	356.52 ppm	357.83 ppm
1992-06	359.44 ppm	357.07 ppm	356.87 ppm
1992-07	357.15 ppm	356.58 ppm	355.18 ppm
1992-08	354.99 ppm	356.67 ppm	353.66 ppm
1992-09	353.01 ppm	356.36 ppm	353.58 ppm
1992-10	353.40 ppm	356.72 ppm	354.81 ppm
1992-11	354.42 ppm	356.48 ppm	355.99 ppm
1992-12	355.68 ppm	356.50 ppm	356.74 ppm
1993-01	357.10 ppm	357.06 ppm	357.21 ppm
1993-02	357.42 ppm	356.54 ppm	357.55 ppm
1993-03	358.59 ppm	356.88 ppm	357.96 ppm
1993-04	359.39 ppm	356.71 ppm	358.43 ppm
1993-05	360.30 ppm	357.14 ppm	358.38 ppm
1993-06	359.64 ppm	357.24 ppm	357.35 ppm
1993-07	357.45 ppm	356.87 ppm	355.73 ppm
1993-08	355.76 ppm	357.44 ppm	354.45 ppm
1993-09	354.14 ppm	357.51 ppm	354.48 ppm
1993-10	354.23 ppm	357.60 ppm	355.71 ppm
1993-11	355.53 ppm	357.65 ppm	356.96 ppm
1993-12	357.03 ppm	357.92 ppm	357.86 ppm
1994-01	358.36 ppm	358.25 ppm	358.48 ppm
1994-02	359.04 ppm	358.21 ppm	359.00 ppm
1994-03	360.11 ppm	358.41 ppm	359.36 ppm
1994-04	361.36 ppm	358.59 ppm	359.71 ppm
1994-05	361.78 ppm	358.59 ppm	359.74 ppm
1994-06	360.94 ppm	358.57 ppm	358.80 ppm
1994-07	359.51 ppm	358.91 ppm	357.27 ppm
1994-08	357.59 ppm	359.29 ppm	356.06 ppm
1994-09	355.86 ppm	359.31 ppm	356.02 ppm
1994-10	356.21 ppm	359.63 ppm	357.27 ppm
1994-11	357.65 ppm	359.80 ppm	358.69 ppm
1994-12	359.10 ppm	359.96 ppm	359.54 ppm
1995-01	360.04 ppm	359.91 ppm	360.13 ppm
1995-02	361.00 ppm	360.18 ppm	360.62 ppm
1995-03	361.98 ppm	360.37 ppm	361.08 ppm
1995-04	363.44 ppm	360.76 ppm	361.55 ppm
1995-05	363.83 ppm	360.73 ppm	361.47 ppm
1995-06	363.33 ppm	360.98 ppm	360.62 ppm
1995-07	361.78 ppm	361.11 ppm	359.00 ppm
1995-08	359.33 ppm	360.93 ppm	357.74 ppm
1995-09	358.32 ppm	361.70 ppm	358.06 ppm
1995-10	358.14 ppm	361.52 ppm	359.43 ppm
1995-11	359.61 ppm	361.75 ppm	360.77 ppm
1995-12	360.82 ppm	361.67 ppm	361.65 ppm
1996-01	362.20 ppm	361.98 ppm	362.14 ppm
1996-02	363.36 ppm	362.47 ppm	362.50 ppm
1996-03	364.28 ppm	362.64 ppm	362.82 ppm
1996-04	364.69 ppm	361.99 ppm	363.14 ppm
1996-05	365.25 ppm	362.23 ppm	363.29 ppm
1996-06	365.06 ppm	362.82 ppm	362.88 ppm
1996-07	363.69 ppm	362.98 ppm	361.57 ppm
1996-08	361.55 ppm	363.13 ppm	360.07 ppm
1996-09	359.69 ppm	363.14 ppm	359.70 ppm
1996-10	359.72 ppm	363.12 ppm	360.67 ppm
1996-11	361.04 ppm	363.18 ppm	361.78 ppm
1996-12	362.39 ppm	363.23 ppm	362.63 ppm
1997-01	363.24 ppm	363.03 ppm	363.26 ppm
1997-02	364.21 ppm	363.40 ppm	363.63 ppm
1997-03	364.65 ppm	363.02 ppm	364.02 ppm
1997-04	366.49 ppm	363.82 ppm	364.50 ppm
1997-05	366.77 ppm	363.87 ppm	364.50 ppm
1997-06	365.73 ppm	363.56 ppm	363.58 ppm
1997-07	364.46 ppm	363.74 ppm	361.93 ppm
1997-08	362.40 ppm	363.98 ppm	360.40 ppm
1997-09	360.44 ppm	363.83 ppm	360.40 ppm
1997-10	360.97 ppm	364.28 ppm	361.93 ppm
1997-11	362.65 ppm	364.71 ppm	363.61 ppm
1997-12	364.51 ppm	365.28 ppm	364.68 ppm
1998-01	365.39 ppm	365.19 ppm	365.19 ppm
1998-02	366.10 ppm	365.29 ppm	365.47 ppm
1998-03	367.36 ppm	365.73 ppm	365.93 ppm
1998-04	368.79 ppm	366.17 ppm	366.58 ppm
1998-05	369.56 ppm	366.68 ppm	366.86 ppm
1998-06	369.13 ppm	366.95 ppm	366.26 ppm
1998-07	367.98 ppm	367.29 ppm	364.83 ppm
1998-08	366.10 ppm	367.69 ppm	363.79 ppm
1998-09	364.16 ppm	367.51 ppm	364.03 ppm
1998-10	364.54 ppm	367.82 ppm	365.34 ppm
1998-11	365.67 ppm	367.70 ppm	366.60 ppm
1998-12	367.30 ppm	368.05 ppm	367.47 ppm
1999-01	368.35 ppm	368.13 ppm	368.11 ppm
1999-02	369.28 ppm	368.46 ppm	368.51 ppm
1999-03	369.84 ppm	368.24 ppm	368.90 ppm
1999-04	371.15 ppm	368.62 ppm	369.29 ppm
1999-05	371.12 ppm	368.31 ppm	369.21 ppm
1999-06	370.46 ppm	368.29 ppm	368.36 ppm
1999-07	369.61 ppm	368.93 ppm	366.69 ppm
1999-08	367.06 ppm	368.63 ppm	365.33 ppm
1999-09	364.95 ppm	368.28 ppm	365.45 ppm
1999-10	365.52 ppm	368.80 ppm	366.75 ppm
1999-11	366.88 ppm	368.86 ppm	368.04 ppm
1999-12	368.26 ppm	368.93 ppm	368.88 ppm
2000-01	369.45 ppm	369.24 ppm	369.39 ppm
2000-02	369.71 ppm	368.99 ppm	369.65 ppm
2000-03	370.75 ppm	369.24 ppm	369.97 ppm
2000-04	371.98 ppm	369.44 ppm	370.35 ppm
2000-05	371.75 ppm	368.87 ppm	370.24 ppm
2000-06	371.87 ppm	369.66 ppm	369.31 ppm
2000-07	370.02 ppm	369.36 ppm	367.91 ppm
2000-08	368.27 ppm	369.87 ppm	366.76 ppm
2000-09	367.15 ppm	370.46 ppm	366.71 ppm
2000-10	367.18 ppm	370.42 ppm	367.91 ppm
2000-11	368.53 ppm	370.48 ppm	369.28 ppm
2000-12	369.83 ppm	370.46 ppm	370.10 ppm
2001-01	370.76 ppm	370.60 ppm	370.69 ppm
2001-02	371.69 ppm	370.95 ppm	371.18 ppm
2001-03	372.63 ppm	371.06 ppm	371.59 ppm
2001-04	373.55 ppm	370.99 ppm	371.90 ppm
2001-05	374.03 ppm	371.11 ppm	371.76 ppm
2001-06	373.40 ppm	371.18 ppm	370.81 ppm
2001-07	371.68 ppm	371.08 ppm	369.45 ppm
2001-08	369.78 ppm	371.39 ppm	368.32 ppm
2001-09	368.34 ppm	371.61 ppm	368.36 ppm
2001-10	368.61 ppm	371.85 ppm	369.71 ppm
2001-11	369.94 ppm	371.92 ppm	371.05 ppm
2001-12	371.42 ppm	372.09 ppm	371.97 ppm
2002-01	372.70 ppm	372.48 ppm	372.51 ppm
2002-02	373.37 ppm	372.49 ppm	372.91 ppm
2002-03	374.30 ppm	372.61 ppm	373.38 ppm
2002-04	375.19 ppm	372.54 ppm	373.73 ppm
2002-05	375.93 ppm	372.98 ppm	373.71 ppm
2002-06	375.69 ppm	373.46 ppm	372.84 ppm
2002-07	374.16 ppm	373.58 ppm	371.41 ppm
2002-08	372.03 ppm	373.70 ppm	370.35 ppm
2002-09	370.92 ppm	374.28 ppm	370.67 ppm
2002-10	370.73 ppm	374.06 ppm	371.95 ppm
2002-11	372.43 ppm	374.52 ppm	373.28 ppm
2002-12	373.98 ppm	374.72 ppm	374.26 ppm
2003-01	375.07 ppm	374.82 ppm	374.94 ppm
2003-02	375.82 ppm	374.95 ppm	375.47 ppm
2003-03	376.64 ppm	374.99 ppm	375.91 ppm
2003-04	377.92 ppm	375.24 ppm	376.39 ppm
2003-05	378.78 ppm	375.73 ppm	376.54 ppm
2003-06	378.46 ppm	376.22 ppm	375.71 ppm
2003-07	376.88 ppm	376.37 ppm	374.16 ppm
2003-08	374.57 ppm	376.27 ppm	372.93 ppm
2003-09	373.34 ppm	376.65 ppm	373.09 ppm
2003-10	373.31 ppm	376.65 ppm	374.36 ppm
2003-11	374.84 ppm	376.99 ppm	375.66 ppm
2003-12	376.17 ppm	376.93 ppm	376.52 ppm
2004-01	377.17 ppm	376.96 ppm	377.21 ppm
2004-02	378.05 ppm	377.19 ppm	377.73 ppm
2004-03	379.06 ppm	377.40 ppm	378.16 ppm
2004-04	380.54 ppm	377.80 ppm	378.47 ppm
2004-05	380.80 ppm	377.66 ppm	378.40 ppm
2004-06	379.87 ppm	377.57 ppm	377.51 ppm
2004-07	377.65 ppm	377.12 ppm	375.96 ppm
2004-08	376.17 ppm	377.90 ppm	374.49 ppm
2004-09	374.43 ppm	377.80 ppm	374.39 ppm
2004-10	374.63 ppm	377.99 ppm	375.73 ppm
2004-11	376.33 ppm	378.49 ppm	377.20 ppm
2004-12	377.68 ppm	378.48 ppm	378.17 ppm
2005-01	378.63 ppm	378.37 ppm	378.73 ppm
2005-02	379.91 ppm	379.10 ppm	379.27 ppm
2005-03	380.95 ppm	379.45 ppm	379.87 ppm
2005-04	382.48 ppm	379.84 ppm	380.32 ppm
2005-05	382.64 ppm	379.49 ppm	380.42 ppm
2005-06	382.40 ppm	380.07 ppm	379.60 ppm
2005-07	380.93 ppm	380.38 ppm	377.94 ppm
2005-08	378.93 ppm	380.61 ppm	376.73 ppm
2005-09	376.89 ppm	380.20 ppm	376.76 ppm
2005-10	377.19 ppm	380.50 ppm	378.07 ppm
2005-11	378.54 ppm	380.69 ppm	379.53 ppm
2005-12	380.31 ppm	381.09 ppm	380.52 ppm
2006-01	381.58 ppm	381.33 ppm	381.33 ppm
2006-02	382.40 ppm	381.58 ppm	381.95 ppm
2006-03	382.86 ppm	381.32 ppm	382.34 ppm
2006-04	384.80 ppm	382.11 ppm	382.68 ppm
2006-05	385.22 ppm	382.06 ppm	382.63 ppm
2006-06	384.24 ppm	381.93 ppm	381.76 ppm
2006-07	382.65 ppm	382.10 ppm	380.07 ppm
2006-08	380.60 ppm	382.27 ppm	378.49 ppm
2006-09	379.04 ppm	382.35 ppm	378.63 ppm
2006-10	379.33 ppm	382.66 ppm	380.08 ppm
2006-11	380.35 ppm	382.52 ppm	381.44 ppm
2006-12	382.02 ppm	382.84 ppm	382.39 ppm
2007-01	383.10 ppm	382.88 ppm	383.03 ppm
2007-02	384.12 ppm	383.22 ppm	383.54 ppm
2007-03	384.81 ppm	383.17 ppm	384.01 ppm
2007-04	386.73 ppm	383.95 ppm	384.27 ppm
2007-05	386.78 ppm	383.56 ppm	384.12 ppm
2007-06	386.33 ppm	384.06 ppm	383.26 ppm
2007-07	384.73 ppm	384.25 ppm	381.55 ppm
2007-08	382.24 ppm	383.95 ppm	380.30 ppm
2007-09	381.20 ppm	384.56 ppm	380.69 ppm
2007-10	381.37 ppm	384.72 ppm	382.10 ppm
2007-11	382.70 ppm	384.90 ppm	383.45 ppm
2007-12	384.19 ppm	385.07 ppm	384.46 ppm
2008-01	385.78 ppm	385.54 ppm	385.23 ppm
2008-02	386.06 ppm	385.20 ppm	385.74 ppm
2008-03	386.28 ppm	384.72 ppm	386.15 ppm
2008-04	387.33 ppm	384.71 ppm	386.53 ppm
2008-05	388.78 ppm	385.69 ppm	386.49 ppm
2008-06	387.99 ppm	385.68 ppm	385.58 ppm
2008-07	386.62 ppm	386.05 ppm	384.10 ppm
2008-08	384.32 ppm	385.98 ppm	382.77 ppm
2008-09	383.41 ppm	386.69 ppm	382.54 ppm
2008-10	383.22 ppm	386.50 ppm	383.67 ppm
2008-11	384.41 ppm	386.58 ppm	385.18 ppm
2008-12	385.79 ppm	386.64 ppm	386.27 ppm
2009-01	387.17 ppm	386.86 ppm	387.03 ppm
2009-02	387.70 ppm	386.81 ppm	387.48 ppm
2009-03	389.04 ppm	387.54 ppm	387.71 ppm
2009-04	389.76 ppm	387.15 ppm	387.99 ppm
2009-05	390.36 ppm	387.24 ppm	387.95 ppm
2009-06	389.70 ppm	387.46 ppm	386.96 ppm
2009-07	388.24 ppm	387.77 ppm	385.01 ppm
2009-08	386.29 ppm	387.99 ppm	383.63 ppm
2009-09	384.95 ppm	388.22 ppm	383.93 ppm
2009-10	384.64 ppm	387.88 ppm	385.49 ppm
2009-11	386.23 ppm	388.36 ppm	386.94 ppm
2009-12	387.63 ppm	388.43 ppm	387.84 ppm
2010-01	388.91 ppm	388.62 ppm	388.62 ppm
2010-02	390.41 ppm	389.47 ppm	389.33 ppm
2010-03	391.37 ppm	389.85 ppm	389.68 ppm
2010-04	392.67 ppm	390.12 ppm	389.98 ppm
2010-05	393.21 ppm	390.09 ppm	389.95 ppm
2010-06	392.38 ppm	390.10 ppm	389.01 ppm
2010-07	390.41 ppm	389.93 ppm	387.35 ppm
2010-08	388.54 ppm	390.21 ppm	386.23 ppm
2010-09	387.03 ppm	390.32 ppm	386.70 ppm
2010-10	387.43 ppm	390.72 ppm	388.25 ppm
2010-11	388.87 ppm	390.99 ppm	389.62 ppm
2010-12	389.99 ppm	390.80 ppm	390.34 ppm
2011-01	391.50 ppm	391.19 ppm	390.85 ppm
2011-02	392.05 ppm	391.12 ppm	391.29 ppm
2011-03	392.80 ppm	391.27 ppm	391.66 ppm
2011-04	393.44 ppm	390.83 ppm	392.05 ppm
2011-05	394.41 ppm	391.24 ppm	392.07 ppm
2011-06	393.95 ppm	391.64 ppm	391.13 ppm
2011-07	392.72 ppm	392.24 ppm	389.19 ppm
2011-08	390.33 ppm	392.04 ppm	387.86 ppm
2011-09	389.28 ppm	392.60 ppm	388.26 ppm
2011-10	389.19 ppm	392.53 ppm	389.83 ppm
2011-11	390.48 ppm	392.64 ppm	391.21 ppm
2011-12	392.06 ppm	392.86 ppm	392.04 ppm
2012-01	393.31 ppm	393.07 ppm	392.61 ppm
2012-02	394.04 ppm	393.20 ppm	393.20 ppm
2012-03	394.59 ppm	392.99 ppm	393.72 ppm
2012-04	396.38 ppm	393.65 ppm	393.99 ppm
2012-05	396.93 ppm	393.73 ppm	393.88 ppm
2012-06	395.91 ppm	393.63 ppm	392.84 ppm
2012-07	394.56 ppm	394.12 ppm	391.00 ppm
2012-08	392.59 ppm	394.37 ppm	389.89 ppm
2012-09	391.32 ppm	394.75 ppm	390.55 ppm
2012-10	391.27 ppm	394.64 ppm	392.16 ppm
2012-11	393.20 ppm	395.25 ppm	393.56 ppm
2012-12	394.57 ppm	395.27 ppm	394.39 ppm
2013-01	395.78 ppm	395.62 ppm	395.07 ppm
2013-02	397.03 ppm	396.23 ppm	395.69 ppm
2013-03	397.66 ppm	396.07 ppm	396.28 ppm
2013-04	398.64 ppm	395.79 ppm	396.74 ppm
2013-05	400.02 ppm	396.64 ppm	396.75 ppm
2013-06	398.81 ppm	396.48 ppm	395.96 ppm
2013-07	397.51 ppm	397.13 ppm	394.48 ppm
2013-08	395.39 ppm	397.27 ppm	393.24 ppm
2013-09	393.72 ppm	397.24 ppm	393.21 ppm
2013-10	393.90 ppm	397.25 ppm	394.50 ppm
2013-11	395.36 ppm	397.35 ppm	395.96 ppm
2013-12	397.03 ppm	397.78 ppm	396.87 ppm
2014-01	398.04 ppm	397.74 ppm	397.51 ppm
2014-02	398.27 ppm	397.45 ppm	397.97 ppm
2014-03	399.91 ppm	398.37 ppm	398.27 ppm
2014-04	401.51 ppm	398.63 ppm	398.63 ppm
2014-05	401.96 ppm	398.56 ppm	398.69 ppm
2014-06	401.43 ppm	399.10 ppm	397.72 ppm
2014-07	399.27 ppm	398.85 ppm	396.13 ppm
2014-08	397.18 ppm	399.07 ppm	395.02 ppm
2014-09	395.54 ppm	399.11 ppm	395.12 ppm
2014-10	396.16 ppm	399.58 ppm	396.38 ppm
2014-11	397.40 ppm	399.49 ppm	397.86 ppm
2014-12	399.08 ppm	399.81 ppm	398.83 ppm
2015-01	400.18 ppm	399.92 ppm	399.56 ppm
2015-02	400.55 ppm	399.77 ppm	400.12 ppm
2015-03	401.74 ppm	400.22 ppm	400.57 ppm
2015-04	403.35 ppm	400.46 ppm	400.96 ppm
2015-05	404.15 ppm	400.70 ppm	400.91 ppm
2015-06	402.97 ppm	400.65 ppm	400.06 ppm
2015-07	401.46 ppm	401.11 ppm	398.38 ppm
2015-08	399.11 ppm	401.04 ppm	397.07 ppm
2015-09	397.82 ppm	401.43 ppm	397.34 ppm
2015-10	398.49 ppm	401.89 ppm	398.80 ppm
2015-11	400.27 ppm	402.24 ppm	400.36 ppm
2015-12	402.06 ppm	402.72 ppm	401.66 ppm
2016-01	402.73 ppm	402.45 ppm	402.62 ppm
2016-02	404.25 ppm	403.40 ppm	403.26 ppm
2016-03	405.06 ppm	403.54 ppm	403.85 ppm
2016-04	407.60 ppm	404.77 ppm	404.36 ppm
2016-05	407.90 ppm	404.41 ppm	404.40 ppm
2016-06	406.99 ppm	404.59 ppm	403.62 ppm
2016-07	404.59 ppm	404.24 ppm	402.10 ppm
2016-08	402.45 ppm	404.41 ppm	400.78 ppm
2016-09	401.23 ppm	404.85 ppm	400.96 ppm
2016-10	401.79 ppm	405.23 ppm	402.41 ppm
2016-11	403.72 ppm	405.74 ppm	403.76 ppm
2016-12	404.64 ppm	405.33 ppm	404.67 ppm
2017-01	406.36 ppm	406.04 ppm	405.33 ppm
2017-02	406.66 ppm	405.80 ppm	405.91 ppm
2017-03	407.54 ppm	406.05 ppm	406.32 ppm
2017-04	409.22 ppm	406.37 ppm	406.60 ppm
2017-05	409.89 ppm	406.37 ppm	406.64 ppm
2017-06	409.08 ppm	406.68 ppm	405.85 ppm
2017-07	407.33 ppm	407.01 ppm	404.11 ppm
2017-08	405.32 ppm	407.31 ppm	402.57 ppm
2017-09	403.57 ppm	407.17 ppm	402.66 ppm
2017-10	403.82 ppm	407.23 ppm	404.16 ppm
2017-11	405.31 ppm	407.36 ppm	405.70 ppm
2017-12	407.00 ppm	407.71 ppm	406.75 ppm
2018-01	408.15 ppm	407.83 ppm	407.53 ppm
2018-02	408.52 ppm	407.61 ppm	408.23 ppm
2018-03	409.59 ppm	408.06 ppm	408.77 ppm
2018-04	410.45 ppm	407.65 ppm	409.07 ppm
2018-05	411.44 ppm	407.98 ppm	408.94 ppm
2018-06	410.99 ppm	408.60 ppm	408.06 ppm
2018-07	408.90 ppm	408.60 ppm	406.49 ppm
2018-08	407.16 ppm	409.17 ppm	405.11 ppm
2018-09	405.71 ppm	409.30 ppm	405.18 ppm
2018-10	406.19 ppm	409.56 ppm	406.65 ppm
2018-11	408.21 ppm	410.24 ppm	408.13 ppm
2018-12	409.27 ppm	409.99 ppm	409.19 ppm
2019-01	411.03 ppm	410.69 ppm	409.92 ppm
2019-02	411.96 ppm	410.97 ppm	410.34 ppm
2019-03	412.18 ppm	410.71 ppm	410.89 ppm
2019-04	413.54 ppm	410.92 ppm	411.33 ppm
2019-05	414.86 ppm	411.47 ppm	411.34 ppm
2019-06	414.15 ppm	411.74 ppm	410.53 ppm
2019-07	411.96 ppm	411.64 ppm	408.88 ppm
2019-08	410.17 ppm	412.10 ppm	407.65 ppm
2019-09	408.76 ppm	412.26 ppm	407.92 ppm
2019-10	408.74 ppm	412.09 ppm	409.44 ppm
2019-11	410.47 ppm	412.50 ppm	410.88 ppm
2019-12	411.97 ppm	412.71 ppm	411.76 ppm
2020-01	413.59 ppm	413.22 ppm	412.44 ppm
2020-02	414.32 ppm	413.41 ppm	412.97 ppm
2020-03	414.72 ppm	413.35 ppm	413.44 ppm
2020-04	416.42 ppm	413.92 ppm	413.86 ppm
2020-05	417.28 ppm	413.98 ppm	413.81 ppm
2020-06	416.58 ppm	414.16 ppm	412.88 ppm
2020-07	414.58 ppm	414.19 ppm	411.17 ppm
2020-08	412.75 ppm	414.60 ppm	409.74 ppm
2020-09	411.50 ppm	414.91 ppm	410.00 ppm
2020-10	411.49 ppm	414.79 ppm	411.66 ppm
2020-11	413.10 ppm	415.12 ppm	413.25 ppm
2020-12	414.23 ppm	414.91 ppm	414.14 ppm
2021-01	415.49 ppm	415.23 ppm	414.73 ppm
2021-02	416.72 ppm	415.80 ppm	415.20 ppm
2021-03	417.61 ppm	416.17 ppm	415.49 ppm
2021-04	419.01 ppm	416.58 ppm	415.81 ppm
2021-05	419.09 ppm	415.88 ppm	416.01 ppm
2021-06	418.93 ppm	416.48 ppm	415.20 ppm
2021-07	416.90 ppm	416.48 ppm	413.45 ppm
2021-08	414.42 ppm	416.27 ppm	412.15 ppm
2021-09	413.26 ppm	416.63 ppm	412.38 ppm
2021-10	413.90 ppm	417.14 ppm	413.83 ppm
2021-11	414.97 ppm	416.93 ppm	415.58 ppm
2021-12	416.67 ppm	417.37 ppm	416.60 ppm
2022-01	418.13 ppm	417.86 ppm	417.18 ppm
2022-02	419.24 ppm	418.32 ppm	417.64 ppm
2022-03	418.76 ppm	417.31 ppm	418.16 ppm
2022-04	420.19 ppm	417.67 ppm	418.58 ppm
2022-05	420.97 ppm	417.70 ppm	418.45 ppm
2022-06	420.94 ppm	418.47 ppm	417.43 ppm
2022-07	418.85 ppm	418.41 ppm	415.67 ppm
2022-08	417.15 ppm	419.03 ppm	414.40 ppm
2022-09	415.91 ppm	419.30 ppm	414.62 ppm
2022-10	415.74 ppm	418.97 ppm	416.13 ppm
2022-11	417.47 ppm	419.51 ppm	417.84 ppm
2022-12	418.99 ppm	419.79 ppm	418.91 ppm
2023-01	419.48 ppm	419.19 ppm	419.37 ppm
2023-02	420.31 ppm	419.34 ppm	419.65 ppm
2023-03	420.99 ppm	419.54 ppm	419.98 ppm
2023-04	423.35 ppm	420.83 ppm	420.48 ppm
2023-05	424.00 ppm	420.71 ppm	420.54 ppm
2023-06	423.68 ppm	421.25 ppm	419.56 ppm
2023-07	421.83 ppm	421.45 ppm	417.92 ppm
2023-08	419.68 ppm	421.61 ppm	416.78 ppm
2023-09	418.50 ppm	421.98 ppm	417.17 ppm
2023-10	418.82 ppm	422.07 ppm	418.84 ppm
2023-11	420.46 ppm	422.41 ppm	420.40 ppm
2023-12	421.86 ppm	422.59 ppm	421.50 ppm
2024-01	422.80 ppm	422.51 ppm	422.20 ppm
2024-02	424.55 ppm	423.59 ppm	422.79 ppm
2024-03	425.38 ppm	423.93 ppm	423.38 ppm
2024-04	426.51 ppm	423.99 ppm	423.85 ppm
2024-05	426.90 ppm	423.61 ppm	423.93 ppm
2024-06	426.91 ppm	424.48 ppm	423.23 ppm
2024-07	425.55 ppm	425.17 ppm	421.61 ppm
2024-08	422.99 ppm	424.92 ppm	420.27 ppm
2024-09	422.03 ppm	425.51 ppm	420.58 ppm
2024-10	422.38 ppm	425.63 ppm	422.33 ppm
2024-11	423.85 ppm	425.80 ppm	424.07 ppm
2024-12	425.40 ppm	426.14 ppm	425.20 ppm
2025-01	426.65 ppm	426.36 ppm	426.01 ppm
2025-02	427.09 ppm	426.12 ppm	426.46 ppm
2025-03	428.15 ppm	426.69 ppm	426.66 ppm
2025-04	429.64 ppm	427.12 ppm	427.03 ppm
2025-05	430.51 ppm	427.22 ppm	427.04 ppm
2025-06	429.61 ppm	427.18 ppm	425.90 ppm
2025-07	427.87 ppm	427.49 ppm	424.09 ppm
2025-08	425.48 ppm	427.41 ppm	422.86 ppm
2025-09	424.37 ppm	427.85 ppm	423.06 ppm
2025-10	424.87 ppm	428.12 ppm	424.66 ppm
2025-11	426.46 ppm	428.40 ppm	426.38 ppm
2025-12	427.49 ppm	428.22 ppm	427.31 ppm
2026-01	428.62 ppm	428.32 ppm	428.02 ppm
2026-02	429.35 ppm	428.39 ppm	428.45 ppm
2026-03	430.15 ppm	428.69 ppm	428.50 ppm
2026-04	431.12 ppm	428.60 ppm	428.68 ppm
2026-05	432.34 ppm	429.05 ppm	428.62 ppm
2026-06	431.43 ppm	429.00 ppm	427.79 ppm
2026-07	429.13 ppm	428.74 ppm	426.10 ppm
2026-08	427.55 ppm	429.48 ppm	n/a
2026-09	426.07 ppm	429.55 ppm	n/a

Yearly Increase

Change in the Mauna Loa annual mean

Change in the Mauna Loa annual mean from the previous year, 1960 to 2025, in ppm.

Yearly increase in the Mauna Loa annual mean, in ppm
Year	Change from the previous year (ppm)
1959	n/a
1960	0.93 ppm
1961	0.73 ppm
1962	0.81 ppm
1963	0.54 ppm
1964	0.63 ppm
1965	0.42 ppm
1966	1.33 ppm
1967	0.81 ppm
1968	0.87 ppm
1969	1.57 ppm
1970	1.06 ppm
1971	0.64 ppm
1972	1.14 ppm
1973	2.22 ppm
1974	0.51 ppm
1975	0.94 ppm
1976	0.90 ppm
1977	1.81 ppm
1978	1.57 ppm
1979	1.43 ppm
1980	1.92 ppm
1981	1.36 ppm
1982	1.36 ppm
1983	1.67 ppm
1984	1.72 ppm
1985	1.48 ppm
1986	1.26 ppm
1987	1.70 ppm
1988	2.38 ppm
1989	1.51 ppm
1990	1.25 ppm
1991	1.25 ppm
1992	0.84 ppm
1993	0.67 ppm
1994	1.75 ppm
1995	2.01 ppm
1996	1.77 ppm
1997	1.14 ppm
1998	2.96 ppm
1999	1.70 ppm
2000	1.17 ppm
2001	1.61 ppm
2002	2.13 ppm
2003	2.53 ppm
2004	1.72 ppm
2005	2.28 ppm
2006	2.11 ppm
2007	1.93 ppm
2008	1.81 ppm
2009	1.81 ppm
2010	2.46 ppm
2011	1.75 ppm
2012	2.21 ppm
2013	2.68 ppm
2014	2.07 ppm
2015	2.20 ppm
2016	3.40 ppm
2017	2.35 ppm
2018	1.96 ppm
2019	2.93 ppm
2020	2.56 ppm
2021	2.20 ppm
2022	2.12 ppm
2023	2.55 ppm
2024	3.53 ppm
2025	2.74 ppm

Average yearly increase at Mauna Loa by decade
Decade	Average increase per year (ppm)
1960s	0.86
1970s	1.22
1980s	1.64
1990s	1.53
2000s	1.91
2010s	2.40
2020s (6 years)	2.62

The Seasonal Cycle

Average of the latest ten complete years

How far each calendar month's Mauna Loa mean sits above the lowest month of the year, September, averaged over the latest ten complete years. The trend line is removed first, so the bars show the yearly cycle alone.

Average seasonal cycle of CO2 at Mauna Loa: each month's level above the lowest month, in ppm
Month	Above the September level (ppm)
January	3.79 ppm
February	4.42 ppm
March	4.95 ppm
April	6.10 ppm
May	6.84 ppm
June	5.91 ppm
July	3.86 ppm
August	1.56 ppm
September	0.00 ppm
October	0.18 ppm
November	1.49 ppm
December	2.77 ppm

Recent Years

Annual means

Annual mean CO2 at Mauna Loa and the global mean, latest years
Year	Mauna Loa (ppm)	Change (ppm)	Global mean (ppm)	Change (ppm)
2025	427.35	2.74	425.62	2.83
2024	424.61	3.53	422.79	3.44
2023	421.08	2.55	419.35	2.27
2022	418.53	2.12	417.08	2.38
2021	416.41	2.20	414.70	2.25
2020	414.21	2.56	412.45	2.38
2019	411.65	2.93	410.07	2.46
2018	408.72	1.96	407.61	2.39
2017	406.76	2.35	405.22	2.15
2016	404.41	3.40	403.07	3.42
2015	401.01	2.20	399.65	2.31
2014	398.81	2.07	397.34	1.94

Download the Data

Source: NOAA Global Monitoring Laboratory, Earth System Research Laboratories (gml.noaa.gov/ccgg/trends). Mauna Loa CO2 data are from NOAA and Scripps (before 1974 the monthly values come from the Scripps Institution of Oceanography). The global means of CO2, methane and nitrous oxide are from the NOAA GML cooperative air sampling network (methane and nitrous oxide: Lan, Thoning and Dlugokencky, doi:10.15138/P8XG-AA10). (US Government open data (NOAA GML, citation requested)) Data as of 2026-11-12. Levels are as published by NOAA; the yearly increases, decade averages and seasonal cycle are computed by this site.