*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970003003
1970001001
1971000000
1972000000
1973000000
1974000000
1975003003
1976001001
1977002002
1978000000
1979000000
1980000000
1981001001
1982003003
1983000000
1984003003
1985002002
1986022004
198714140019
198800190019
198904210025
199002020022
199131340020
19921189700197
19933398500406
19943100716001026
199506741100685
19962792600800
19971347800356
19980725200727
199901681300181
200009391200951
200104741400488
200206211100632
200314191700437
20040756600762
200512941700312
200622931600311
200714383200471
200802372000257
2009124340059
201012468100328
20110557100126
20122116400122
201352433600284
201401331700150
201512110014
2016060006
2017010001
Total2996405480010217