*Excludes Observations that spanned multiple years

Pre 19705
19700
19714
197220
197315
19740
19750
19761
19776
19780
19792
19801
19815
19820
19832
19842
198519
19868
198752
1988210
198926
1990105
1991299
1992352
1993232
199469
1995208
199676
199726
199839
199955
200049
2001165
200257
200312
200436
200521
200614
200718
200813
200910
201075
201175
201237
201330
201446
201544
201667
201760
201835
201953
20200
20210
Total2756