COBCH0312 Invalid arithmetic statement

An arithmetic statement which you have used in the Procedure Division does not conform to the rules of COBOL syntax. These statements must begin with an arithmetic verb (for example SUBTRACT or DIVIDE), followed by the relevant numeric literals or identifiers which the verb will act upon when the program is executed. The statement which you have specified is not a valid one.

Resolution:

Ensure that the arithmetic statement you want to use conforms to the relevant rules.