*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970500117
1970100203
1971100102
1972100102
1973200103
1974200103
1975200305
1976200204
1977400307
1978400206
1979400105
1980200103
1981300003
1982400307
1983500106
1984300508
1985300104
19868107319
19876009419
198880012121
198970122535
199081041326
199140211825
1992910131740
199380313103127
199490020274303
1995120313310338
199670314199223
1997100076784
1998801117494
199930051523
2000110174362
2001110076987
200240017116137
20035021693116
200440110163178
2005800171641
2006902214577
20077002976112
2008400332663
2009200341450
20103014951104
20111005944104
201200054449
2013000225981
2014000113243
2015000729
2016000505
2017000101
2018000000
Total22432054019872774