# File lib/spreadsheet/biffwriter.rb, line 27
   def store_bof(type = 0x0005)
      record  = 0x0809
      length  = 0x0008
      build   = 0x096C
      year    = 0x07C9

      header  = [record,length].pack("vv")
      data    = [BIFF_Version,type,build,year].pack("vvvv") 

      prepend(header, data)
   end