The SUBTRACT statement subtracts one, or the sum of two or more,
  numeric items from one or more items.  It stores the result in one or
  more items.

  Format 1 -

   SUBTRACT { num } ... FROM { rsult [ ROUNDED ] } ...

      [ ON SIZE ERROR stment ] [ NOT ON SIZE ERROR stment ]

      [ END-SUBTRACT ]

1  –  num

  is a numeric literal or the identifier of an elementary numeric item.

2  –  rsult

  is the identifier of an elementary numeric item.  It is the resultant
  identifier.

3  –  stment

  is an imperative statement.