Suppose that in 2012 the expected dividends of the stocks in a broad market index equaled $278 million when the discount rate was 8% and the expected growth rate of the dividends equaled 6%. Using the constant-growth formula for valuation, if interest rates increase to 10%, the value of the market will change by _____%. Type your answer as a percentage and not as decimal (i.e., 5.2 and not 0.052). Do not type the percentage symbol. Round your answer to the nearest two decimals if needed