*Excludes Observations that spanned multiple years

Pre 19704
19700
19712
19721
19730
19740
19751
19761
19771
19780
19790
19800
19810
19820
19830
19840
19850
19861
19871
19880
19890
19900
19910
19920
19930
19940
19950
19960
19974
19980
19990
20000
20010
20020
20030
20040
20050
20060
20070
20080
20090
20100
20110
20120
20131
20140
20150
20160
20170
20181
20190
20200
20210
20220
20230
Total18