Year	Number
1971	17367
1972	15634
1974	12236
1976	17336
1977	11174
1979	15693
1982	14831
1991	8758
1992	11072
1993	12687
1995	10600
1996	12094
2003	12298
2008	2890
2009	8093
2010	4216
2011	2290
2012	4303