*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19904
19913
19923
19934
19942
19956
19963
19972
19985
19991
20000
20014
20022
20033
200410
200512
20065
20076
200812
20091
20102
20110
20120
20131
20140
20150
20160
20170
Total91