*Excludes Observations that spanned multiple years

Pre 19703
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19802
19812
19820
19830
19840
19850
19862
19870
19880
19890
19904
19910
19922
19930
19941
19950
19960
19971
19980
19990
20000
20010
20023
20030
20040
20050
20061
20070
20081
20090
20100
20110
20120
20130
20140
20150
20160
20170
Total22