*Excludes Observations that spanned multiple years

Pre 19705
19700
19711
19721
19730
19740
19751
19760
19771
19780
19793
19805
19814
19823
19831
19841
19856
19860
19871
198878
1989141
1990131
1991118
1992199
1993226
1994318
1995254
1996369
1997344
1998380
1999325
2000160
200135
200228
200331
200413
20057
200614
200719
200820
200938
201072
201142
201222
201335
201412
201513
20168
20171
20187
20192
20203
Total3498