*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
197214
19733
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19852
198618
198713
198838
19899
19907
199115
19920
19934
19945
19957
19962
19976
19982
199913
20008
200125
20029
20030
20041
20052
20061
20071
20080
20090
20100
20111
20120
20130
20140
20151
20165
20171
20180
20190
Total213