*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
198713
19882
19890
19901
199151
199223
19931
19940
19950
19960
19970
19980
19990
20000
20010
20020
20033
20040
20051
20060
20070
20080
20090
20100
20110
20120
20130
20140
20155
20162
20171
20180
20190
Total103