Year annual % 1961 2.81015139962967 1962 13.560758554931668 1963 1.9311502938706968 1964 5.583012996522058 1965 12.62135922330097 1966 9.213362068965516 1967 18.40862640073296 1968 16.118088209035175 1969 12.122610077400173 1970 13.573191917344793 1971 7.966026647345329 1972 26.235925732607562 1973 20.307746832452228 1974 45.788633852952 1975 25.951807634667517 1976 23.34656880439578 1977 28.777828358370726 1978 27.21840202671425 1979 16.79567587593945 1980 34.40203014631328 1981 15.845948953100239 1982 20.452577582129734 1983 26.000338278644954 1984 25.250496198210808 1985 20.56037205029569 1986 11.83620662285297 1987 11.570175202022424 1988 21.985005337061857 1989 21.368601757580688 1990 26.124426830190494 1991 13.17810337838068 1992 19.443668534469268 1993 30.328806214552873 1994 12.232450434591605 1995 9.163453003798509 1996 10.19707821609762 1997 8.234069185578557 1998 10.505346211630217 1999 13.435496254686132 2000 18.960029202178003 2001 23.536479315668977 2002 18.5107981571375 2003 7.808539499092665 2004 10.723235049063426 2005 11.37611232650035 2006 7.285060964701703 2007 12.433260176008037 2008 25.181802889200235 2009 8.613515470424524 2010 13.470884226602898 2011 -7.809881231172332