*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970402219
1970000819
197100013619
197200042648
197310011012
19740008210
1975000202
1976100304
1977101619
1978000101
1979100304
1980200103
198100011011
198220013015
1983100304
1984300104
1985100618
1986200417
1987100304
1988101518
19891009212
19901017312
1991006111027
19921028213
19931037516
199420328538
199520052660
199610030940
1997101201537
199820045552
199900215623
200010428841
200100032436
200210040041
200320015219
200410026330
200520313119
200630040245
200710225331
2008000729
200900011011
201030544355
201140428238
201200217019
201300131032
201400628236
2015001607
2016000325
2017000101
2018000000
Total51050773122996