U.S. retail sales of new vehicles are expected to fall 25% in September as inventory levels remain low despite consumer spending staying strong, J.D. Power and LMC Automotive reported in a joint forecast.

The organizations expect U.S. new vehicle retail sales to drop 888,900 units in September, from 1,182,788 a year ago.

These results show “there are simply not enough vehicles available to meet consumer demand,” J.D. Power said in a statement.

Demand soars for personal transportation, with consumers expected to spend billions in September. But production has slowed because of semiconductor shortages and supply chain disruptions. LMC Automotive predicted supply chain gaps will persist until 2023.

The gap between demand and supply also has led to record vehicle prices. J.D. Power noted the average transaction price in September will reach an all-time high of $42,802. Used vehicle prices also are heating up after cooling in late-June and July, J.D. Power added.

The seasonally adjusted annualized rate for new vehicle sales will hit 12.2 million, down four million units from 2020 and about 800,000 units less than 2019.