11.   In part, cost is driving the trend.

12.   Low interest rates and continued economic growth are driving the trends, Fannie Mae said.

13.   Longer life spans, a strong economy and an unwillingness to fade into retirement all drive the trend.

14.   Money, of course, is driving this trend.

15.   More choices, good prices, better quality are driving the trend.

16.   One of the things driving this trend is the celebrity market.

17.   Several factors drive this trend.

18.   Something other than ignorance must be driving the trend.

19.   The growth of the two-career family, and the increasing self-confidence of skilled workers in the current hot economy, are driving the trend.

20.   The growing purity and decreasing cost of heroin is driving the trend, city officials said.