Traffic on the Maine Turnpike has become increasingly sparse as Mainers have followed government guidance to stay near home and limit nonessential travel.

Daily traffic dropped by 20 percent between Monday and Friday of last week, according to data provided by the Maine Turnpike Authority. Last Friday, there were about 155,700 vehicles on the road, less than half the number on the same day a week before.

Weekend traffic was down by almost 50 percent from the same period last year. On Sunday, fewer than 81,000 vehicles drove on the turnpike, almost 57 percent below the same day in 2019.

“It really just shows a record of how rapidly commerce has deteriorated,” said turnpike authority Executive Director Peter Mills. “It is a very good proxy for economic collapse.”

Even the impact a multi-day snowstorm can have on vehicle traffic is an inaccurate comparison to the current persistent decline. It is likely fewer cars will be on the road after Wednesday, following Gov. Janet Mills’ move to impose new restrictions on nonessential businesses.

“We don’t have these extended periods, when traffic is off by 50 percent now for a week at a time,” Peter Mills said. “I’m trying to remember anything to compare it to and I can’t.”

There also has been a double-digit decline in traffic on state roads in general, based on initial observations by the Maine Department of Transportation. Still, the department would not release traffic data because it is incomplete and too early to indicate a trend, said state traffic engineer Steve Landry.

At first glance, it seems vehicle counts are down more on the interstate and urban parts of southern Maine compared with rural parts of the state, he said.

“We are seeing a reduction, but we don’t know how long it is going to last or if this is a blip,” Landry said.

A sudden decline in passenger traffic on the turnpike drove overall volume down, said turnpike authority Chief Financial Officer Doug Davidson in an interview last week.

Passenger cars were down nearly 19 percent as of last Thursday, as many office employees working from home avoided their daily commute and other businesses closed their doors. The most noticeable drop was on a typically busy stretch of highway around Portland between Biddeford-Saco and Falmouth, Davidson said.

At the same time, commercial traffic was still flowing up and down the highway, he added. Over the week, truck traffic was down just 1 percent from the year before, as supermarkets and other stores restocked depleted shelves.

“Goods are flowing, people are not,” Davidson said.

Turnpike records mirror national traffic trends tracked by Inrix, a location and mobility data and analytics company based in Washington. In a Monday post, the company said personal vehicle travel was down 30 percent nationwide for the seven days beginning March 14, compared with the last week in February.

Before the sudden impact of the coronavirus pandemic, the Maine Turnpike was heading into another record-breaking year for traffic and toll revenue.

Turnpike traffic has increased by 13 percent in five years. Last year, it hit a record at nearly 90 million fare transactions. Until this month, yearly traffic had increased by almost 7 percent in 2020, according to Davidson.

Maine’s transportation networks ground to a halt last week as businesses eliminated nonessential travel and people heeded government warnings to stay home and avoid groups in an effort to limit the spread of coronavirus.

By the end of last week, airplane boardings at Portland International Jetport dropped by roughly 70 percent compared with the year before. The Amtrak Downeaster passenger rail and Concord Coach Lines bus company dramatically reduced service between Maine communities and Boston in reaction to absent customer demand.

It is too early to tell what a sustained drop in traffic will mean for the turnpike’s finances, Peter Mills said. The authority’s board of directors is expected to meet this week to vote on awarding a $28 million contract to widen 5 miles of highway from four to six lanes north of Scarborough.

“My present instinct is to go to my board on Thursday and recommend going ahead with the contract,” he said. “It is a good way to keep commerce moving in southern Maine.”