Inventory estimates down but still high

The number of unsold vehicles in the U.S. was at its lowest point in 12 months, starting August at an estimated 3,798,400 vehicles, but thanks to a weaker selling rate, the days' supply figure associated with that inventory — 71 days — is the highest it's been on Aug. 1 for more than 27 years.

For the first time, the monthly inventory figures were estimated for all domestic automakers after FCA US joined General Motors and Ford Motor Co. in switching to quarterly sales reporting from monthly.

Dealers and automakers had an estimated 2,859,600 unsold light trucks on hand to start the month, a 73-day supply, and an estimated 938,800 cars, representing a 64-day supply, according to the Automotive News Data Center. It was the first time since the beginning of November 2011 that the car total was below 1 million.

The beginning of August is historically one of the leanest inventory times of the year in the U.S., largely because domestic assembly plants traditionally use June and July to retool for model changeovers.

The days' supply figure is determined by the selling rate from the previous month, so it is volatile. For example, there were almost 100,000 more vehicles in inventory at the same point in 2017, but the days' supply figure for that month was 69 because of a higher selling rate at the time.