According to Spader Cos., sales rose 3.5 percent for the average used boat dealer since last year. Spader attributes this rise to a 14.2 percent increase in pre-owned boat sales. New boat sales are up only 0.6 percent from 2006.

New boat inventories at dealerships were up only 1.7 percent from last year, while pre-owned boat inventories increased 5 percent.

Spader Cos. is a training and consulting firm that tracks North American boat dealers to compile an average profile, then compares year-over-year trends.