Mortgage rates were little changed Friday in quiet trading. This morning, the Institute for Supply Management services index rose to 57.6, beating forecast. Readings above 50.0 indicate expansion in the services sector of the economy. Fed Chairwoman Janet Yellen will be speaking in Chicago today at 1:00 PM, her last scheduled public remarks before the next Fed meeting on March 14-15. Expectations for a short-term rate increase have surged this week to about 80% following comments by several Fed officials. No other key data will be released today.