*Excludes Observations that spanned multiple years

Pre 19702
19700
19712
19720
19730
19740
19751
19760
19770
19780
19791
19800
19810
19821
19838
19841
19851
198639
19873
198811
19897
199012
19910
199211
199314
199412
19956
19962
199729
199810
19992
20000
20016
200213
200321
200453
200524
20062
20073
20082
20091
20103
20114
20120
20130
20140
20156
20166
20170
Total319