The current financial information of Westgate Noodle House is as follows: Monthly sales: 1,000 units Price: 20 Yuan per unit Variable costs: 10 Yuan per unit Fixed costs: 5,500 Yuan per month Westgate's main competitor, Eastgate, used to offer the same price as Westgate. Eastgate has just increased its price per unit by 5% because its variable cost has increased by 1 yuan per unit. What is the minimum potential sales increase that would discourage Westgate from raising price by 5% as well? (5 points)