*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19801
19810
19820
19830
19840
19850
19860
19872
19880
19890
199012
19912
19923
19930
19940
19950
19960
19971
19981
199924
200049
200119
200210
20034
20048
20050
20066
20071
20084
20094
20101
20111
20124
20130
20141
20150
20166
20174
20181
20198
20201
20215
20228
20234
20240
Total196