The MTA has a new report out that illustrates how much bridge and tunnel tolls have outpaced inflation over the past four decades.

Cash tolls today on four major crossings — the RFK Bridge (which is really the Triborough Bridge), the Bronx-Whitestone Bridge, the Throgs Neck Bridge, and the Queens-Midtown Tunnel — are $6.50, 26 times their 25-cent rate of 1971. By contrast, inflation has pushed the general price of goods and services to 5.5 times what they were back then.

So, bridge and tunnel tolls have exceeded inflation by 4.7 times.

If subway and bus fares had gone up by a similar proportion, the single-ride today, which costs $2.25, would cost $7.80, 26 times the 1971 fare of 30 cents.

The MTA offers volume discounts, but not enough to offset this huge increase in costs.

Driving toll hikes is operating expenses. Over the past decade, labor costs have grown 87 percent, 3.2 times faster than inflation, while non-labor costs have grown by 35 percent, roughly tracking inflation.

Since 9/11, the MTA has hired 265 security people, but cut 200 toll-booth people. Cuts have been more than offset by growing wage and benefits costs.

The good news is that the MTA’s crossings are “geometrically and functionally adequate.”

The bad news is that they’re old — the average age is 63 — so it requires an increasing amount of money to keep them that way.

As the MTA notes, “the aging of the [tunnel and bridge] facilities will influence the overall upkeep and capital improvements that will be necessary to maintain the infrastructure.” From 2010 through 2014, keeping bridges and tunnels in good shape will cost $2.5 billion.