*Excludes Observations that spanned multiple years

Pre 19704
19700
19710
19720
19730
19740
19750
19760
19770
19781
19790
19801
19810
19822
19831
19840
19850
19861
19871
19882
19890
19900
19910
19925
19931
19940
19950
19961
19970
19981
19990
20000
200112
20020
20030
20041
20051
20060
20070
20084
200916
20100
20110
201214
20131
20140
20150
20160
20170
Total70