*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19731
19740
19759
19761
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19901
19910
19922
19930
19940
19950
19960
19970
19984
19991
20002
20011
20023
20030
20042
20059
20060
20070
20082
20091
20100
20116
20125
201312
20140
20150
20160
20170
Total62