*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
19910
19922
19934
19942
19952
19969
19970
19983
19992
20001
20012
20024
20032
20042
20052
20060
20071
20087
20092
20100
20119
20124
20132
20140
20150
20160
20170
Total66