*Excludes Observations that spanned multiple years

Pre 197015
19705
19710
19725
19730
19745
19755
19760
19770
19785
197910
19800
19815
198210
198317
19845
198520
198620
198724
198811
198910
199012
199166
199269
199370
199469
199558
199693
1997151
1998177
1999202
2000322
2001127
2002124
2003142
2004142
2005186
2006218
2007386
2008363
2009471
2010580
2011411
2012273
2013337
201415
20150
20160
20170
Total5236