*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
199137
199211
19931
19942
19954
19969
19970
19981
19998
20007
20016
20023
20031
20040
20050
20060
20071
20080
20091
20101
20110
20120
20131
20140
20150
20160
20170
20181
20190
Total95