*Excludes Observations that spanned multiple years

Pre 19704
19700
19710
19720
19730
19740
19750
19760
19773
19780
19791
19800
19810
19820
19830
19840
19850
19861
19873
198850
19890
19900
199128
19922
199326
19945
199529
19969
19972
19982
199966
200042
200138
20028
20035
200444
20050
20061
20070
20085
20093
20101
20111
20121
20131
20141
20150
20160
20179
20183
20195
20200
20212
Total401