Hurrell PC-Based North Atlantic Oscillation Index (MAM) 1899 -1.26 1900 -0.39 1901 -0.28 1902 -0.50 1903 1.01 1904 1.32 1905 0.57 1906 0.14 1907 0.29 1908 0.49 1909 -1.80 1910 0.35 1911 0.98 1912 1.32 1913 2.23 1914 1.70 1915 -1.13 1916 -1.50 1917 -1.62 1918 0.57 1919 -0.12 1920 0.97 1921 1.77 1922 0.19 1923 0.06 1924 -2.08 1925 0.29 1926 -0.20 1927 0.34 1928 -0.60 1929 0.09 1930 -0.29 1931 -1.29 1932 -1.22 1933 -0.80 1934 0.96 1935 -1.25 1936 -0.34 1937 -0.78 1938 1.17 1939 0.22 1940 -1.33 1941 -0.73 1942 -0.83 1943 1.91 1944 0.05 1945 0.19 1946 0.38 1947 0.27 1948 1.39 1949 0.52 1950 0.34 1951 -1.91 1952 -1.60 1953 -0.60 1954 -0.35 1955 -0.94 1956 0.87 1957 -1.08 1958 -1.56 1959 0.59 1960 -0.90 1961 -0.28 1962 -1.76 1963 0.38 1964 0.08 1965 -0.48 1966 -0.58 1967 1.23 1968 0.21 1969 -0.97 1970 -0.49 1971 -0.55 1972 0.64 1973 -0.29 1974 0.01 1975 -0.60 1976 1.32 1977 0.23 1978 0.15 1979 -0.33 1980 -0.73 1981 -0.96 1982 1.39 1983 -0.44 1984 -0.69 1985 -0.14 1986 1.57 1987 0.16 1988 -0.88 1989 1.47 1990 2.40 1991 0.11 1992 1.39 1993 -0.03 1994 1.48 1995 -0.77 1996 -1.17 1997 0.48 1998 0.21 1999 -0.47 2000 0.21 2001 -0.79 2002 1.03 2003 0.73 2004 0.94 2005 -1.33 2006 -1.12 2007 1.42 2008 -1.06 2009 1.22 2010 -1.30 2011 1.77 2012 0.33 2013 -1.71 2014 0.77 2015 2.25 2016 0.34 2017 -0.09 2018 0.09 2019 0.54 2020 0.72 2021 -0.22 2022 0.24 2023 -1.27 2024 -1.04 2025 0.79