10. The average price of a home in W County rose more than 12% last year but the number of sales fell nearly 15%. Its the old law of supply and demand, said a spokesman for the Board of Realtors. The number of sales is down because there's a higher demand for properties but there isn't a corresponding number to sell Draw a diagram to illustrate the case of a shift in demand and/or supply curves that is consistent with the observed change in prices and quantities