Update: This story has been updated to include INDOT traffic volume data from Indianapolis' surrounding counties.

Traffic around the Indianapolis area has fallen considerably, almost certainly due to changes brought on to stop coronavirus. There were also fewer crashes in March 2020 than in March the previous two years, Indiana State Police say.

Traffic volume on Monday, March 30, was 39% lower than it was on Monday, March 2, according to an IndyStar analysis of Indiana Department of Transportation data. The department summarized data from 12 sites located in nine Central Indiana counties, including Marion County. Sites included four interstates, four state roads, two U.S. routes and Binford Boulevard.

More than 535,000 vehicles traveled the monitored roads on March 2. Four weeks later, that total was more than 200,000 vehicles lower: about 325,000.

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The decrease between these two Mondays was as large as 47% at one spot on Interstate 65, just south of the Lafayette Road exit, IndyStar found. The data collected at this spot was not included in the summarized data provided by INDOT.

Much changed over that four-week span because of COVID-19. Many Hoosiers were asked to work from home. Others were furloughed or laid off. Students began learning at home. Many of these changes were prompted by Gov. Eric Holcomb's statewide stay-at-home order, which took effect at 11:59 p.m. March 24.

Traffic volume had already fallen before the order took effect. On Monday, March 23, nearly 28% fewer vehicles were on the roads than on Monday, March 9, according to INDOT data presented at a news conference with the governor.

Heavy truck traffic declined less than smaller vehicle traffic.

Fewer crashes and fatalities

"In my career I have not seen a decline in vehicle traffic for this extended amount of time," Indiana State Police Sgt. John Perrine, who has had a 17-year career, told IndyStar.

Perrine said there has been "an obvious reduction in traffic." Vehicle crash totals fell as well.

In March 2019, Indiana saw 15,855 crashes. The total dropped to 11,170 this March.

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Traffic fatalities held steady: There were 46 traffic fatalities in both March 2019 and March 2020, Perrine said. March 2018 had 73 fatalities.

March traffic totals can be difficult to compare, he said, because March snow storms can cause an increase in the total some years. The National Weather Service in Indianapolis did not record a significant winter storm in March 2019, though two such storms occurred in 2018.

Less traffic means less work for some.

JR Cook, who has owned Cook's Towing Service for three decades, guesses his business is down about 70%.

Cook has not laid off or furloughed any of his 23 employees, but he said employees are not getting overtime anymore.

“In my lifetime I’ve never seen nothing like this," Cook said. "Nothing."

Email IndyStar digital producer Ethan May at emay@indystar.com. Follow him on Twitter @EthanMayJ.