*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
19875
19880
19892
19900
19910
19922
19931
19941
19951
19960
19971
19980
19991
20000
20012
20020
20030
20040
20055
20060
20070
20085
20091
201037
201151
20123
201310
201411
20151
20162
20171
20180
Total143