*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19861
19873
198810
19897
19906
199116
19929
199313
19940
19956
19960
19971
19980
19999
20004
20010
20024
20030
20041
20051
20060
20070
20083
20090
20101
20111
20121
20130
20141
20154
20160
20170
20180
Total102