*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
19873
19880
19891
19908
19915
199222
19931
19940
199534
19963
19972
19980
19990
20000
20013
20020
20030
20041
20050
20060
20070
20081
20090
20103
20116
20120
20130
20140
20151
20161
20170
20181
20190
Total96