*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19781
19791
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19900
19910
199232
199313
19941
19951
19961
19971
19980
199922
20006
20018
20021
20030
20041
20050
20060
20070
20081
20090
20105
201112
20121
20130
20140
20150
20162
20172
20180
20192
20205
20216
20223
20232
20241
Total131