*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
19870
19880
19897
19901
19910
19924
19937
19945
19957
19960
19973
19980
19990
20000
20010
20022
20031
20041
20055
20060
20071
20083
20090
20100
20111
20121
20130
20141
20151
20161
20173
20180
20190
Total55