This story appears in the Aug. 18 print edition of Transport Topics.

U.S. retail sales of heavy-duty trucks jumped 22.5% in July to 18,793 units from a year ago, marking the first back-to-back monthly percentage gains above 20% in more than two years, WardsAuto.com reported.

The total was second-highest this year, trailing June’s 19,373, which  was the third-highest since 2006 and a 21.6% year-over-year increase.

July marked the fourth-highest monthly sales total since that boom year, and the year-over-year increase was second-highest this year behind March’s 25.6% gain.

Year-to-date, sales are up 15.1% over the same period last year at 118,583 big rigs, the highest through July since 2006, according to Ward’s.

An analyst said sales are likely to remain strong.

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