*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 197062000062
1970300003
1971700007
1972300003
1973500005
1974600107
1975700007
1976600006
197710000010
1978600006
1979800008
1980800109
198112000012
198210000010
1983600006
1984400004
1985300003
198611001012
19879005014
19889002011
1989120021235
1990110001122
19916006012
19929013114
199313001155169
199410005279294
199515003241259
199611014352368
199714007525546
199810028252272
199911003205219
200015003239257
200110003196209
20026005207218
20038004241253
200410004319333
200512007262281
2006100124311346
200713109264287
2008600152546
200940132138
201030055361
201110044045
201281011020
201310012013
201401010415
201500012012
2016000505
2017000000
2018000000
Total4243632640954854