*Excludes Observations that spanned multiple years

Pre 19700
19700
19711
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19891
19904
19914
19927
19935
19943
199519
199639
199738
19988
19992
20008
20010
20024
20033
20041
20051
20064
20070
20080
20090
20100
20110
20120
20130
20144
20151
20160
20170
Total157