*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19821
19831
19840
19850
19866
19870
19880
19890
19900
19910
19922
19938
19940
19951
19960
19971
19981
19996
20000
20011
20020
20035
200439
20059
20061
20070
20081
20090
20100
20110
20120
20130
20140
20150
20161
20170
Total84