*Excludes Observations that spanned multiple years

Pre 197053
19700
19710
19720
19730
19740
19750
19761
19770
19781
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19900
19910
19920
19931
19940
19950
19960
19973
19981
19990
20000
20010
20020
20030
20040
20050
20061
20070
20080
200912
201039
201120
20122
20131
20142
20150
20162
20170
20184
20190
Total143