The biggest story in auto rental so far this year is the sky-high prices to rent a car. The causality is clear — the continuing semiconductor chip shortage is canceling sold fleet orders, exacerbating already tight supply at a time when demand is gaining steam as the economy exits the pandemic.

What do the numbers say? According to data collected by Bobit Business Media, parent of Auto Rental News, U.S. rental fleet sales for April came in at 67,618 units. When compared to last year’s sales of 32,994, that’s a 104.9% increase. But last year, as we’re well aware, was anything but normal.

The first quarter of 2020 began as one of the best in recent history for car rental from a revenue standpoint. Fleet sales orders, which are placed months before, roughly track with strong rental demand and revenues. Automakers sold 494,960 units to rental fleets in the first quarter ending March 31, 2020.

By April 2020, however, the first full month of the pandemic’s grip, the bottom fell out of the U.S. economy. In fact, April 2020 likely set a generational low for car rental fleet sales. From April 2021 forward, the year-over-year comps in car rental — and most industries — are meaningless to track performance.

A more worthy comparison is to the pre-pandemic window of 2019. Comparing the first four months of 2021 to 2019, fleet sales were 693,213 units from January to April in 2019 compared to only 360,491 for the same period in 2021, for a 48% decline.

The 2019 to 2021 comparison declines are accelerating. April 2019 sales of 141,385 units compared to April 2021 represents an unprecedented 52.2%. The gap may widen further. May is usually a strong month for rental fleets to stock up on units for the summer travel season, though the semiconductor chip shortage is not abating.