*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 1970000044
1970000000
1971000033
1972000011
1973000022
1974001023
1975000033
1976000044
1977000033
1978000011
19790070411
1980001023
1981001045
1982000066
1983002002
19840050510
1985001034
19860070613
19870090413
19880090817
19890050611
199000340539
199100380341
199200480452
199300500959
1994004701360
199500460450
199600430144
199700480553
199800310839
199900260935
200001290939
200100340741
200200490453
200300320436
200400330639
200500150621
200600210425
200701140621
200800261431
200900550459
201000460147
201100600262
201200181322
201300220123
2014004004
2015002002
2016002002
2017000000
Total0292121931118