*Excludes Observations that spanned multiple years

Pre 19700
19700
19712
19721
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19831
19842
19858
198623
198798
198835
19899
199014
199190
199227
199336
19943
199590
199641
199756
19982
199931
200024
200143
200216
20031
20046
20053
20066
20072
20082
20091
20100
20111
20123
20134
20143
20153
20162
20171
20180
20190
20200
Total690