*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000000
1974000101
1975000101
1976000101
1977000101
1978000000
1979000202
1980000000
1981000000
1982000000
1983000000
1984000000
1985000000
1986000123
1987000314
1988000000
19890017210
1990000134
19910022610
1992000268
199300521926
199400055459
199500115153
199600004242
199700131418
199800104243
1999000112
200000056267
200100116365
200200026365
200300185362
200400275160
20050017412
2006001164259
2007002113548
200800010010
2009001719
2010001161229
2011003141027
2012000033
201300071522
201400051116
2015000505
2016000235
2017001001
2018000000
Total0025157671853