The level at which commercial lending institutions set mortgage interest rates has a significant effect on the volume of buying, selling, and construction of residential and commercial real estate. A researcher collected data on annual average mortgage interest rates (for conventional, fixed-rate, 30-year loans) for the period 1987-2010, and run a linear trend regression of Y (average mortgage interest rate expressed as a percentage) on X (time period, X = 0, 1, 2, ......, n). The estimated equation has a Y-intercept of 10.50 and a slope of -0.24. Based on this information, the forecast value of the average mortgage interest rate in 2018 would be ______ percent. Express your answerwithoutrounding.