*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 19701140010115
1970400004
197110000010
1972700007
1973700007
1974600107
1975600006
19769001010
197710001011
1978900009
197911001012
198010001011
198114000014
198215003018
1983700209
198410003013
1985700007
198618002121
1987210015238
1988200014236
1989180021645
1990140102237
199112017323
199216012423
19931902171351
19942001185392
19951723121145
1996911124265
1997200212229173
1998150413545199
1999150013130176
2000240115835218
200121001185144
20028001051114
2003130012411148
200420001383161
200519011283151
200615032374259
200724101607192
20081612944117
2009140011824156
201017031948222
201120001248152
20122230171254
2013142071390
201401274784
201540141147
2016100203
2017000303
2018000000
Total742112924283993609