On a shopping​ trip, Sofia decided to buy a light blue coat that had a price tag of​ $79.95. When she brought the coat to the​ store's sales​ clerk, Sofia was told that the coat was on​ sale, and she would pay 20 percent less than the price on the tag. After the discount was​ applied, Sofia paid​ $63.96, $15.99 less than the original price. The value of​ Sofia's consumer surplus from this purchase is