*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19741
19751
19760
19770
19780
19792
19803
19812
19820
19830
19840
19853
19861
19873
19880
19890
19901
19910
19920
19931
19941
19950
19961
19975
19982
19993
200018
200123
200225
200343
200448
200554
200668
20078
20087
200912
201016
20113
201218
20130
20144
201511
20162
20170
20180
Total390