Year	Total
1971	519.7
1972	492.6
1973	537.8
1974	524.7
1975	520.8
1976	537
1977	580.4
1978	594.6
1979	565.6
1980	766.2
1981	838.4
1982	910
1983	1117
1984	1132
1985	1114
1986	1235
1987	1239
1988	1024
1989	899.6
1990	1149
1991	1089
1992	1261
1993	1193
1994	1179
1995	1013
1996	980.1
1997	1044
1998	1234
1999	920.1
2000	1028
2001	1210
2002	1237
2003	1163
2004	852.5
2005	1020
2006	784.9
2007	1225
2008	1385
2009	1519