*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19741
19750
19760
19770
19780
19790
19800
19810
19820
19833
19843
19851
19868
19873
19888
19897
19902
199121
19926
199334
199416
199546
19965
199710
19983
199978
20001
200110
200211
200311
20044
200518
20066
20071
20083
20090
201038
201149
201210
20134
20144
20150
20161
20170
Total426