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*Excludes Observations that spanned multiple years

Pre 19704
19700
19717
197278
197315
19740
19750
19761
19770
19780
19791
19800
19811
19821
19830
198425
198540
198684
1987162
1988305
1989135
199073
1991197
1992171
1993242
1994294
1995258
1996182
1997144
199825
199951
200056
200172
200231
200347
2004100
200563
200630
200746
200847
200940
201045
201154
201262
201371
201473
201552
201652
201747
201811
201981
20200
20210
Total3576