*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19815
19821
19831
198411
19850
19860
198713
19880
19890
19902
199133
199218
19935
19942
19951
19961
19971
19981
19990
20003
20011
20020
20032
200410
20050
20064
20075
200817
200914
20100
20111
20120
20131
20140
20150
20160
20170
20185
20190
20200
Total158