Year CO2 (ppm)
1969 323.2
1968 323.7
1965 319.5
1965 318.8
1963 318.2
1962 318.7
1962 317
1962 319.4
1962 317
1953 311.9
1953 311
1953 312.7
1944 309.7
1939 311
1938 310.5
1932 307.8
1924 304.8
1924 304.1
1915 301.3
1912 300.7
1905 296.9
1905 298.5
1898 294.7
1892 294.6
1886 293.7
1882 291.9
1877 288.8
1869 287.4
1861 286.6
1854 284.9
1850 285.2
1840 283
1978 335.2
1978 332
1975 331.2
1973 328.1
1971 324.1
1970 325.2
1970 324.7
1948 309.9
1940 310.5
1934 309.2
1832 284.5
1959 315.7
1954 313.6
1954 314.7
1954 314.1
1948 311.4
1939 309.2
1936 307.9
1929 305.2
1926 305
1905 299
1899 296.5
1891 294.7
1845 286.1
1825 285.1
1796 283.7
1794 281.6
1777 279.5
1760 276.7
1749 277.2
1747 276.9
1720 277.5
1692 276.5
1679 275.9
1647 277.2
1604 274.3
1589 278.7
1570 281.9
1547 282.8
1527 283.2
1499 282.4
1465 279.6
1446 281.7
1387 280
1387 280.4
1327 283.4
1246 281.7
1196 283.9
1146 283.8
1096 282.4
1046 280.3
1006 279.4

** Source:
Etheridge, D.M., Steele, L.P., Langenfelds, R.L., Francey, R.J., Barnola, J.-M. and Morgan V.I.  1998.  Historical CO2 records from the Law Dome DE08, DE08-2, and DSS ice cores.  In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tenn., U.S.A.