*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19726
19738
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19852
19860
19871
19883
19890
19900
19910
19922
19935
19943
19951
19961
19971
19980
19990
200012
200114
20021
20030
20041
20050
20060
20070
20083
20090
20104
20114
20120
20130
20140
20150
201611
20170
20180
20190
Total83