*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970000000
1971000000
1972000000
1973000000
1974000000
1975000000
1976000000
1977000000
1978000000
1979000000
1980000000
1981000000
1982000000
1983000000
1984000000
1985000000
1986000000
1987000000
1988010001
1989000000
1990040004
1991000000
1992000000
1993000000
1994011002
1995000000
1996020002
1997000000
1998200002
1999213006
2000030003
2001030003
2002000000
2003000000
2004000000
2005000000
2006000000
2007000000
2008010001
2009000000
2010000000
2011000000
2012040004
2013001001
2014000000
2015030003
2016020002
2017040004
2018060006
2019080008
2020000000
2021000000
Total44350052