*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19843
19855
19865
19876
19886
19897
199011
19917
19927
19937
19948
19956
199616
199722
199824
19999
200018
200113
200220
200320
200427
200521
200635
200727
200819
200926
201024
201125
201244
201313
201412
20157
20164
20170
20180
Total504