# File lib/wx/groups.rb, line 168
      def initialize(raw)
        raise ArgumentError unless raw =~ /^(M?)(\d+ )?(\d+)(\/(\d+))?SM$/
        @minus = true if $1 == 'M'
        if $4
          d = $3.to_f / $5.to_f
        else
          d = $3.to_f
        end
        if $2
          d += $2.to_f
        end
        super("#{d} mi")
      end