*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000000
1978000000
1979001001
1980000000
1981001001
1982000000
1983000000
1984000000
1985001001
1986003003
1987005005
1988003003
1989003003
1990003003
199100180018
199200100010
1993006006
1994007007
199500100010
199600110011
1997009009
199800120012
1999009009
200000150015
200100170017
200200170017
200300100010
2004006006
200500280028
200600140014
200700120012
2008004004
200900160016
2010008008
201100130013
2012003003
2013004004
2014000000
2015000000
2016000000
2017000000
Total0027900279