*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19841
19852
19867
19873
198826
19893
19904
199117
19922
19932
19940
19950
19962
19976
19983
19994
20003
20011
20021
20035
20040
20053
20067
20073
20083
20091
20100
20110
20120
20132
20140
20151
20161
20172
20180
Total115