Klikstop makes a "gaming" hearing aid that integrates with game controllers. Klikstop has been making these hearing aids at a variable cost of $219.97 each, but expects that variable cost is about to go up by $14.76 per unit. Klikstop sells 32,500 of these hearing aids per year, at a selling price of $267.17. With the expected increase in variable cost, Klikstop is planning to raise the hearing aid's selling price by $29.46 per unit. What is the percent change in Quantity (units sold) such that Klikstop will just break even on these changes in price and variable cost? Be sure to use the correct sign. (Report your answer as a percent. Report 25.5%, for example, as "25.5." Rounding: tenth of a percent.)