*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19781
19790
19800
19810
19820
19830
19840
19850
19860
19870
19882
19890
19901
19910
19920
19930
19940
19950
19960
19971
19980
19992
20000
20012
20020
20030
20040
20050
20060
20070
20083
20091
201054
201155
20124
20132
20140
20150
20161
20170
20180
Total129