*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970100102
1970000000
1971000101
1972000000
1973000000
1974000000
1975000101
1976000000
1977000000
1978000000
1979000101
1980000101
1981100102
1982001001
1983000000
1984000000
1985000101
1986001001
1987000101
1988001102
1989000000
1990000000
1991001135
199200083947
19931025816
199400436269
199500134448
199600021416
1997000112031
1998000707
199900001212
200000012113
200100111214
200200041822
20030007714
200400021315
20050012223226
200600032629
200700064349
20080004152156
200900024547
20100066820
20110043815
201200121518
2013001203
2014000123
2015001304
2016000011
2017000000
2018000000
Total3026109776914