*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19741
19750
19760
19770
19781
19790
19801
19810
19821
19830
19840
19850
19860
19870
19881
19890
19900
19910
19920
19930
19946
19953
19962
19972
19982
19990
20000
20010
20020
20030
20040
20050
20060
20070
20081
20090
20101
20111
20124
20131
20140
20150
20161
20170
20181
20190
20200
20210
20220
Total30