*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000202
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000101
1977000202
1978000101
1979000101
1980000000
1981000101
1982000101
1983000000
1984000000
1985000404
1986000325
1987000718
19880008311
1989000819
199000011314
19910014813
199200165057
199300087987
1994002147692
1995000116677
199600056974
1997001124255
199800089199
199900072633
2000001106677
2001000135366
2002000116778
2003001136478
20040021393108
2005001117890
2006001156682
20070003667103
2008000255782
2009001251642
2010000572077
201100054458
201200024125
201300071623
201400041620
201500010111
2016000213
2017000000
2018000000
Total001244512131670