*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
1982001001
1983000000
1984000000
1985001001
1986000000
198700120012
198800140014
198900180018
1990021003
1991000000
19920120000120
19930270200272
199405681200580
19950511100512
19960616100617
19970507200509
19980199200201
199905620058
200003861100397
20010312800320
200214021300416
200303451300358
20040397600403
200509080098
20060142800150
200703331800351
200812112200234
200904190023
201001274500172
20110772400101
201207050075
20131175500181
201411611200174
20150190010
2016070007
2017000000
Total46089295006388