Year	Number of
1980	316300
1981	324600
1982	326500
1983	117700
1984	91570
1985	111400
1986	149000
1987	179500
1988	194300
1989	170600
1990	156800
1991	194300
1993	73180
1995	13140
1996	4307
1998	89600
1999	20940
2000	11050
2001	34070
2002	52760
2003	70480
2004	94330
2005	142200
2006	176700
2007	230500