March on U.S. new-car sales lots defied greater economic conditions as early spring business buoyed the industry, but the conditions they defied threaten sales growth, analysts said in monthly forecasts.

Though the Cox Automotive and J.D. Power/GlobalData estimates were slightly different, the upshot was the same: Year-over-year, March sales are expected to be down due to last year’s sales surge ahead of trade tariff hikes, but up from February.

Total retail and nonretail sales are projected to hit about 1.4 million for the month, the forecasters said.

Tax returns are likely fueling the sales, but affordability pressures remain a market drag. Average retail transaction prices are expected to be up nearly 3% year-over-year to $45,859, according to J.D. Power, which put average monthly loan payments up an estimated 5% to $805, the highest it has on record for March.

Cox only briefly mentioned the war in the Middle East that the U.S. and Israel opened on Feb. 28, acknowledging its contribution to overall market uncertainty and therefore consumer demand. Despite that cloudiness, it noted recent auto market stability.

“Sales are no longer swinging wildly month to month, but growth is also harder to come by,” said Senior Economist Charlie Chesbrough. “Affordability remains the central challenge for the industry, and that is limiting the market’s ability to expand beyond the mid-15-million range.” 

The two market analysts put the monthly sales pace at different levels but up from February, Cox at 15.8 million units, J.D. Power at 16 million.

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