*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
1972150
197364
19740
19750
19760
19770
19781
19790
19801
19811
19820
19833
198489
198557
1986113
1987180
1988215
198961
1990124
1991134
199297
199371
199423
199510
199614
199719
19983
1999100
2000143
200171
200223
200317
200419
200536
200632
200724
200826
200929
201022
201137
201243
201344
201449
201545
201647
201753
20180
20190
Total2290