*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000101
1970000000
1971000000
1972000000
1973000000
1974000000
1975000303
1976000000
1977000000
1978000000
1979000000
1980000011
1981000000
1982000202
1983000000
1984000000
1985000000
1986000112
198700011415
198800017017
19890007310
199000001414
19910012710
199200413641
19930001112113
19940014355360
19950002271273
19960002370372
19970013212216
19980001303304
199900028890
20000002441443
20010003263266
20020003293296
20030004343347
20040005414419
20050007144151
20060017203211
200700115258274
200800017169186
2009001211436
201000044109153
201100035120155
20120000113113
201300024142166
20140003287119
2015000516
2016000325
2017000011
2018000000
Total001028748945191