*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
19870
19880
19890
19900
19912
19920
19930
19940
19950
19960
19970
19980
19990
20000
20010
20022
20030
20045
20050
20060
20070
20080
20093
20100
20110
20120
20130
20147
20151
20160
20170
20181
20190
20202
20211
20220
20231
20243
Total28