The seasonally adjusted annual rate for new light vehicles rose in March to 15.5 million units on the strength of revived inventory and manufacturer incentives.

The 4% year-over-year bump came on the strongest sales volume of the first quarter, said the National Automobile Dealers Association.

NADA forecasts that sales will ascend as the year continues to total 15.9 million units. It expects inventory to continue to grow before plateauing in the second quarter, then turning back up in the fourth to reach about 2.8 million units at the end of the year.

The quarterly SAAR clocked in at 15.4 million, up 7% year-over-year.

Inventory for the month totaled 2.6 million units, up a dramatic 40% year-over-year. Meanwhile, average incentive spending per unit hit $2,800, up 67%, NADA said, quoting J.D. Power data.

The conditions favored buyers, as the average transaction price was an estimated $44,186, down about 4% year-over-year.

On a quarterly basis, alternative-fuel models represented an 18% share of sales, hybrid sales up the most, by 2.4 percentage points to about 9% of sales.

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