Year Number 1960 -2082 1961 -2271 1962 -2389 1963 -2357 1964 -2049 1965 -1582 1966 -1558 1967 -2078 1968 -2743 1969 -2913 1970 -3059 1971 -3181 1972 -3250 1973 -3289 1974 -3296 1975 -3224 1976 -2980 1977 -2988 1978 -2439 1979 -2649 1980 -2808 1981 -7809 1982 -2887 1983 -2850 1984 -2884 1985 1790 1986 1353 1987 2417 1988 14879 1989 -7701 1990 7169 1991 7496 1992 6012 1993 -6692 1994 -48259 1995 -2501 1996 -2949 1997 -5749 1998 -6058 1999 -6575 2000 -6689 2001 -6832 2002 -7036 2003 -7327 2004 -7656 2005 -8000 2006 -8136 2007 -7997 2008 -10009 2009 -10223 2010 -10467 2011 -10654 2012 -10706 2013 -10662 2014 -10586 2015 -10464 2016 -10295 2017 -10127 2018 -9956 2019 -9796 2020 -4897 2021 -4897 2022 -5733 2023 -5268