Suppose you purchase 629 shares of stock at $28.6 per share with an initial cash investment of $12,190. Suppose the call money rate is 4.39 percent and you are charged a 1.5 percent premium over this rate. Calculate your return on investment (in percent) if the share price one year later is $2.50 below the price when you bought the stock. Ignore dividends. Answer to two decimals.