*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 197020012023
1970100001
1971100001
1972200002
1973200002
1974100102
1975300205
1976610108
1977610007
1978400004
1979300104
1980400004
1981400004
1982500106
1983800008
1984300104
1985400105
1986500106
1987400307
19888004113
1989600309
19909001111
19915107013
1992500409
19937006013
199490011121
1995500409
19965016012
1997300227
19985005010
19995005010
20006009015
200150010015
20021008110
2003200406
20047005315
20052007615
2006300508
20076119017
200870013020
200930012015
201050023028
2011100020030
201281215026
2013300003
2014000213
2015200204
2016100506
2017100001
2018000000
Total2305522116477