*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19752
19760
19770
19789
19795
19800
19810
19827
19830
19847
19853
19862
19872
19887
19891
199013
199171
199259
199370
199467
199577
199692
1997118
1998122
1999138
2000350
2001308
2002210
2003366
2004398
2005413
2006289
2007952
2008636
20091000
20101006
2011777
2012768
2013700
201456
20150
20160
20170
Total9101