*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970001001
1971001001
1972001001
1973001001
1974001001
1975001001
1976001001
1977001001
1978000000
1979002002
1980011002
1981000000
1982002002
1983001001
1984002002
1985002002
1986005005
1987003003
1988023005
1989004004
1990023005
1991125008
1992036009
199306210027
199401210022
199532180023
199603160019
199702100012
199801210022
1999015006
200014200025
200101140015
200200170017
200300120012
200413200024
200501210022
2006009009
200700200020
200801290030
200900130013
201001290030
201105350040
2012010001
2013004004
2014003003
2015000000
2016000000
2017000000
Total64340500454