*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 197010130014
1970000000
1971000000
1972000000
1973000000
1974050005
1975101002
1976014005
1977114130028
197871240032
1979738330078
198048210033
1981116160033
198232140019
198356292900114
1984126225200200
198556120023
198602110013
19871813130044
198852402600118
1989117009
19901180010
1991114660081
1992133190053
199332286500125
19944526000116
199546130023
199614326100107
19977836100151
19981412723900380
19994613710300286
200075806100216
2001528180051
20021548330096
20033816370091
200416320039
200525160023
20061323160052
2007812120032
20082627210074
20091926300075
20102741280096
201133762000129
201214740052
20131630010
2014052007
201513770045
2016013004
2017000000
Total68211851327003194