*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000000
1970100001
1971100001
1972100001
1973100102
1974000000
1975100001
1976100001
1977100001
1978100001
1979000101
1980300003
1981000000
1982100001
1983000101
1984000000
1985100001
1986300205
1987200013
1988500016
1989400015
1990400037
1991300104
1992400318
1993410016
1994300328
19957005113
19963006110
19978012011
1998500308
1999600208
20006006214
20018003112
2002000718
20032005613
2004200215
2005400509
200630012217
200780018228
2008200709
2009000617
201010013014
2011000909
20121008110
2013100809
2014000718
201500011011
2016000101
2017000000
2018000000
Total1121115830302