Auditor General Eugene DePasquale’s decision to give the Pennsylvania Turnpike an earlier-than-expected audit is the right call, given the state of its finances.

Drivers and outside observers, including the Butler Eagle, have warned that the commission is backing itself into a corner with incessant rate hikes that will eventually drive motorists away.

So far those warnings haven’t made an impact on the commission. On Sunday motorists were hit with yet another toll increase — a 6 percent hike that brings the average toll for cash customers to $2.10 and $1.30 for E-ZPass riders.

For context, the average cash toll in 2008 was 75 cents.

In 2018 drivers traveling from the Ohio line to the boarder of New Jersey will pay $55, up from $51.85 last year for cash customers. For E-ZPass holders the increase brings the cost of a trip across the state to $39.25, up from $37.

These toll hikes have become routine business for the commission, which last year projected annual 6 percent increases to toll fees for the next 30 years.

If you run the numbers on that projection you’ll find that, at that rate, the cost of a cross-state turnpike trip in 2044 would be $216.

How can anyone believe this is a sustainable trajectory? At those prices, why wouldn’t people just buy a plane ticket and save themselves time and the hassle of driving?

After all the turnpike, with its ever-present construction zones, is hardly a luxurious — or even an enjoyable — ride.

If raising toll rates were the only way to sustain and improve the road, it might make more sense. But a 2016 audit by DePasquale’s office found that squeezing drivers for cash isn’t helping the turnpike.

In 2007 the commission’s net value peaked at $1.76 billion; by 2015 the organization’s value was pegged at negative $4.11 billion because of — according to DePasquale’s audit — debt, false financial projections, uncollected fines and flat traffic volume.

Meanwhile, late last year the turnpike’s use dropped below projections, adding weight to speculations that the commission’s annual rate increases were driving motorists away.

When he announced the early audit, which will cover June 2015 through May of 2017, last week, DePasquale said the checkup was being conducted earlier than normal “Because I’m that concerned,” about projections that show turnpike use increasing even as toll rates rise every year.

We are as well — heck, everyone should be.

According to the Central Penn Business Journal, the cost of driving a tractor-trailer across Pennsylvania’s turnpike is more than twice as expensive as in New York and Massachusetts, and nearly three times more expensive than in Ohio.

Is it any wonder that some are skeptical about the turnpike’s future?