-                Subtraction or Unary Minus                     MASM Operator

    expression1 - expression2       (Subtraction)
 or
    - expression                    (Unary Minus)

    Subtracts an expression from another, or makes an expression a
    negative expression.

       Notes:     The Subtraction operator's operands can be integers or
                  relocatable memory operands.  If both operands are
                  memory addresses, they both must reside in the same
                  segment.  The result of any subtraction operation is an
                  absolute value.

                  The Unary Minus has a higher precedence then the
                  Subtraction operator.  See 'Operator Precedence' for the
                  order of operator precedence.