Curency format /String.Format

   Dim subtotal As String = price * quatity 'price and  quatity  are Decimal type.
  subtotal = String.Format("{0:c}", subtotal)
 
I  want to get the sub total  in currency format 
ie somedigits.twodigits (eg 100000.50), i dont want $ or any such symble before the digits.
I tried the above code but it fails why?
 
 
 


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