Sales of existing homes, hurt by rising mortgage rates, fell in 28 states from July through September, the peak summer sales season, the National Assn. of Realtors reported. The biggest setbacks were in Colorado, where sales were down 28.3%, and Wyoming, where sales543581548slump in oil and gas exploration caused by falling energy prices. Home resales in California rose 0.4% from a year earlier. Overall, the seasonally adjusted annual rate of sales of existing single-family homes dropped to 3.8 million units during the summer, down 3.3% from the year-ago period.