*Excludes Observations that spanned multiple years

Pre 197011
19701
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19831
19840
19850
19860
19870
19880
19890
19900
19911
19920
19932
19941
19952
19960
19970
19980
19990
20000
20010
20020
20030
20040
20051
20060
20070
20081
20092
20100
20110
20120
20130
20141
20150
20160
20171
20180
20191
20200
20210
20220
20230
20241
Total27