*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970001001
1970000000
1971000000
1972001001
1973001001
1974001001
1975000000
1976000000
1977001001
1978001001
1979001001
1980010001
1981000000
1982002002
1983001001
1984001001
1985004004
1986002002
198701140015
198801150016
198901160017
199011130015
19910550010
1992196500102
19930317300320
199419341800953
19951903500909
19961895300899
19970545800553
19980693400697
19990107600113
20000849800857
200114051000416
200208741000884
20030354700361
20040888600894
20050243600249
20060334400338
200706461400660
200802591600275
200902150017
201011825500238
201101324100173
20120192100193
20130207900216
20140251500256
2015005005
2016060006
2017000000
Total7103343340010675