*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19874
19884
198911
19900
19910
19922
19931
19943
19951
19960
19971
19981
19993
20000
200112
20021
20031
20041
20050
20062
20074
20085
20090
20102
20114
20120
20130
20140
20150
20162
20170
Total65