*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970300104
1970000000
1971000000
1972000000
1973100001
1974200002
1975200002
1976300104
1977300003
1978300003
1979400004
1980400105
1981400004
1982400004
1983200002
1984400004
1985500106
1986500005
1987410005
1988500218
19899009321
19903008213
1991100607
199240314223
1993801131335
19941100274381
199572383252
1996201125873
199780071934
199860061830
19999007016
200070046071
20019005721
200240293550
200380021020
200480053346
200580062438
200690031325
200790184058
200870085671
20091009010
2010100181635
2011100121124
201290013545
201300017421
201400013518
2015000101
2016000101
2017000101
2018000000
Total2073112465401007