*Excludes Observations that spanned multiple years

Pre 19701
19700
19712
19721
19730
19740
19750
19761
19770
19781
19791
19802
19810
19822
19830
19840
19852
19861
19875
19884
198912
199031
1991103
199229
199341
199425
199528
199638
199745
199841
199915
20006
200111
200213
20031
20044
20054
20069
20074
200811
20097
20100
20111
201254
20130
20140
20150
20162
20170
Total558