*Excludes Observations that spanned multiple years

Pre 19708
19700
19710
19720
19731
19740
19752
19760
19770
19780
19790
19800
19810
19822
19830
19841
19853
19861
19871
198816
19894
19903
19915
19920
199327
19940
19954
19961
19971
19981
19998
200012
20019
20023
20032
20040
20050
20060
20076
20083
20093
20102
20110
20120
20131
20140
20151
20162
20170
20184
20192
20205
20213
20224
20233
20241
Total155