21.   According to their analysis, leaves could develop only after a steep drop in the amount of atmospheric carbon dioxide, which plants use in photosynthesis.

22.   After raising fares a half-dozen times last year, airlines have seen a steep drop in the numbers of their bread-and-butter business passengers as the economy has cooled.

23.   Brisk winds, a downpour of rain and a steep drop in the temperature marked the first day of winter Monday.

24.   But analysts said a possible shift in holiday buying does little to account for the steep drop in the sales figures reported Thursday.

25.   But even after the recent rebound from the steep drop, some banks still represent decent values, he said.

26.   But the company said a steep drop in its electronics and telecommunications business will snap that streak.

27.   But the shift came not only from increased exports but also from a steep drop in imports because of the economic woes.

28.   But the spinoff was postponed indefinitely because PCA suffered a steep drop in revenues.

29.   But the steep drop in the stock has persuaded a number of value investors to start or expand positions.

30.   But the steep drops began long before the act passed, and there were clearly other forces at work.