*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19721
19730
19740
19751
19760
19770
19783
19792
19801
19811
19822
19832
19842
19853
19861
198710
198855
198910
19906
199112
199210
199314
19943
19956
19967
19977
19980
199913
20009
200149
20025
20031
20041
20056
200618
200726
20083
20090
201012
201112
20124
201311
201410
201516
201644
201724
201847
201910
20200
Total480