*Excludes Observations that spanned multiple years

  B
b
t
W
w
 
Pre 197000001717
1970000000
1971000011
1972000033
1973000033
1974010023
1975001045
1976030036
1977013048
1978004037
1979002046
1980002068
19810160815
19820060814
1983002035
1984001089
198501001011
198601120720
19870440917
19880190919
198901601118
1990031501634
1991175001169
1992143201047
1993236001277
1994134001761
1995125601069
1996252301040
1997222101843
1998022501542
1999122402047
2000332101845
2001333101754
2002014501056
2003052401241
2004031201530
2005143401857
2006254501769
2007024002062
2008116731082
200900146010156
20102015816167
20115325107266
201213255139299
20130513809152
2014117009
2015004015
2016105006
2017000000
Total3186168754712280