*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 197000012012
1970000000
1971000202
1972000202
1973000000
1974000000
1975000000
1976000101
1977000404
1978000000
1979001607
1980001708
1981001708
1982001708
1983002204
1984002406
19850017210
1986003306
19870045110
19880055111
1989001214
1990002316
1991001528
1992000426
19930028010
199400210214
199500213217
199600415221
19970029011
199800312015
1999001517
20000055010
20010038112
2002000707
200300013215
200400211013
200500216018
2006002305
200700314017
200800213015
2009001228040
2010001026036
201100937147
2012000808
2013000808
2014000000
2015000000
2016000202
2017000000
2018000000
Total009135921471