*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19781
19790
19800
19810
19820
19830
19841
19850
19862
19872
19884
19891
19901
19910
199211
199327
199413
19957
19969
19975
19984
199946
200010
20016
20024
20038
20049
200515
20064
20071
20087
200915
201071
2011100
201241
201335
201445
201542
201650
201731
20180
Total629