*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19845
19851
19863
19875
19880
19890
19900
199110
19920
19932
19949
19950
19960
19970
19981
19992
20005
20010
20024
20031
20041
20054
20061
20077
20081
20090
20100
20110
20121
20130
20140
20150
20160
20170
20181
20190
Total64