*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970001001
1970000000
1971000000
1972100001
1973000000
1974000000
1975000000
1976000000
1977200002
1978100001
1979100102
1980100001
1981100001
1982200103
1983100001
1984200002
1985100001
1986100001
1987100102
1988300003
1989400408
1990300104
1991200507
1992300407
1993200305
1994700209
1995300508
1996300205
1997300609
1998400105
19997004011
20005005010
200170012019
200240010014
2003400307
2004400206
2005400206
20065006011
20076005011
20084008012
20095009014
2010100809
201120030032
2012300205
2013000909
2014000000
2015000101
2016000101
2017000000
2018000000
Total113011530267