*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19782
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19903
19910
19928
19935
19943
19952
19960
19970
19981
19990
20000
20010
20020
20030
20043
20050
20060
20070
20080
20090
20101
20110
20121
20130
20141
20150
20160
20170
Total30