*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19832
19840
19850
19862
19871
19880
19890
19904
19910
19920
19934
19946
199510
19963
19973
19986
19993
20000
20012
20020
20030
20043
20050
20060
20070
20080
20090
20100
20111
20120
20130
20141
20150
20162
20170
20181
20190
20200
Total54