*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19728
19737
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19841
19853
19860
19873
198824
19892
199014
199110
19921
19932
19943
19950
19960
19970
19984
199919
200020
200120
20022
20030
20046
20050
20060
20070
20083
20090
20100
20111
20120
20130
20143
20150
20161
20170
20180
20190
Total157