*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972001001
1973000000
1974000000
1975000000
1976000000
1977000000
1978000000
1979000000
1980000000
1981000000
1982000000
1983000000
1984000000
1985000000
1986000000
1987101002
1988310004
198910140015
199010000010
1991701008
1992600006
1993620008
199416010017
199517100018
199619070026
1997121170030
19985410010
1999630009
2000120003
200115800023
2002111210024
200381090027
200416020018
200523030026
200623120026
200740040044
200823130027
200933110035
201026000026
2011001001
2012011002
2013140005
2014013004
2015000000
2016000000
2017000000
Total338546300455