*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000101
1978000000
1979000101
1980000000
1981000202
1982000000
1983000000
1984000000
1985000101
1986000202
1987000404
1988000404
1989000202
1990000505
199100014014
199200011011
1993000909
1994000909
199500017017
199600011011
199700012012
199800013013
1999000808
200000015015
200100015015
200200027027
200300013013
2004000909
2005000909
200600010010
200700016016
2008000606
200900016016
201000015015
201100018018
2012000505
2013000101
2014000404
2015000404
2016000000
2017000000
2018000000
Total0003090309