Cakes by Jacki is considering adding a line of sugar-free cake options. Current sales revenue is $5,000 per month. With the new line added, revenues are estimated to be $6,500 per month. Ingredients and labor are currently $2,200 a month. Estimated total ingredient and labor costs with the new line are expected to be $3,000 per month. Jacki estimates that the utilities will increase from $500 to $575. Rent and other costs of $1,200 per month are not expected to change. In evaluating whether or not to add the new line, the total differential cost equals ______.