*Excludes Observations that spanned multiple years

Pre 1970176
19702
19710
19725
19735
19740
197516
19762
19772
197815
19793
198019
19812
19823
19831
19840
19850
19860
19871
19880
19891
19900
19910
19920
199323
199424
19958
19961
19970
19980
19990
20000
20010
20020
20030
20040
20054
2006121
20071
20080
200910
201022
20114
20120
20130
20140
20150
20160
20170
Total471