*Excludes Observations that spanned multiple years

Pre 197018
19702
19717
19720
19730
197462
1975109
197661
197725
197838
197930
198025
198126
198230
198347
1984200
1985136
1986111
1987131
198885
198958
199097
199197
1992128
1993143
1994129
1995157
1996155
1997207
1998182
1999232
2000260
2001277
2002141
2003263
2004205
2005168
2006342
2007464
2008411
2009232
2010303
2011210
2012244
2013172
201479
20150
20160
20170
Total6499