Year Percent
1950 2.253
1951 2.211
1952 2.162
1953 2.176
1954 2.237
1955 2.319
1956 2.4
1957 2.463
1958 2.497
1959 2.503
1960 2.496
1961 2.494
1962 2.526
1963 2.618
1964 2.764
1965 2.929
1966 3.078
1967 3.189
1968 3.246
1969 3.252
1970 3.231
1971 3.204
1972 3.185
1973 3.182
1974 3.196
1975 3.215
1976 3.228
1977 3.205
1978 3.124
1979 2.995
1980 2.812
1981 2.604
1982 2.49
1983 2.563
1984 2.787
1985 3.122
1986 3.439
1987 3.433
1988 2.894
1989 1.897
1990 0.658
1991 -0.538
1992 -1.336
1993 -1.433
1994 -0.794
1995 0.268
1996 1.33
1997 2.155
1998 2.651
1999 2.803
2000 2.795
2001 2.796
2002 2.79
2003 2.719
2004 2.595
2005 2.434
2006 2.257
2007 2.092
2008 1.963
2009 1.869
2010 1.791
2011 1.711
2012 1.624
2013 1.535
2014 1.445
2015 1.354
2016 1.268
2017 1.195
2018 1.14
2019 1.101
2020 1.073
2021 1.046
2022 1.017
2023 0.983
2024 0.941
2025 0.899
2026 0.858
2027 0.818
2028 0.78
2029 0.743
2030 0.706
2031 0.671
2032 0.636
2033 0.604
2034 0.573
2035 0.544
2036 0.516
2037 0.488
2038 0.462
2039 0.437
2040 0.413
2041 0.388
2042 0.365
2043 0.342
2044 0.319
2045 0.296
2046 0.273
2047 0.25
2048 0.226
2049 0.202
2050 0.177
2051 0.153
2052 0.128
2053 0.101
2054 0.075
2055 0.048
2056 0.022
2057 -0.004
2058 -0.031
2059 -0.058
2060 -0.084
2061 -0.11
2062 -0.136
2063 -0.161
2064 -0.185
2065 -0.209
2066 -0.233
2067 -0.255
2068 -0.275
2069 -0.294
2070 -0.312
2071 -0.329
2072 -0.344
2073 -0.359
2074 -0.373
2075 -0.385
2076 -0.397
2077 -0.408
2078 -0.418
2079 -0.427
2080 -0.434
2081 -0.441
2082 -0.448
2083 -0.453
2084 -0.458
2085 -0.462
2086 -0.465
2087 -0.469
2088 -0.471
2089 -0.473
2090 -0.474
2091 -0.476
2092 -0.478
2093 -0.478
2094 -0.478
2095 -0.478
2096 -0.478
2097 -0.478
2098 -0.477
2099 -0.477