*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19791
19802
19810
19820
19830
19840
19850
19860
19870
19882
19893
19902
199129
199236
199333
19946
19950
19960
19970
19980
19990
20001
20010
20020
20030
20040
20056
20060
20070
20081
20092
20102
20112
20120
201316
20140
20151
20161
20170
20181
20190
20200
20210
20220
Total147