Graffiti is on the express track back into New York’s subway landscape, MTA data obtained by The Post shows.

After holding at around 200 markings in stations and on trains per year in the first half of the decade, the number tripled to 619 in 2018, and sits at 537 as of Dec. 18 this year, the figures show.

“There’s a lot more going on now, I think, than five years ago,” confirmed one New Jersey-based graffiti writer, who declined to be identified — or reveal whether they’d ever turned the city’s subway system into their canvas.

“The floodgates open from time to time, and the internet helps more people think that they can pull it off,” they continued, noting, however, that most serious artists eschew the notoriety that comes with posting their handiwork to social media.

Regardless of who’s responsible, the MTA’s statistics bear out the street art’s subterranean resurgence.

Instances of spray paint on train exteriors have followed a similar trajectory in recent years, surging from 25 in 2014, to 91 in 2017 and 86 last year — though so far, only 38 instances have been logged in 2019, incident reports obtained by The Post show.

Also up in recent years are “major graffiti hits” — markings for which the MTA elects to take a train out of service for cleaning.

There were 377 such incidents in 2017, and 443 last year, and 285 as of Dec. 15, 2019, the MTA figures said.

Each major hit lightens the MTA’s already scraped-clean pockets, with the agency spending a total $348,000 so far this year to clean the 285 majorly bombed trains, data shows.

Sometimes categorized among major hits is political graffiti, which is also on the rise.

The MTA has logged a total of 13 anti-President Trump scrawls since 2016, after tallying just seven anti-Obama tags since the start of his two-terms in 2008, data shows.

Among the most popular targets overall is the M train, tagged a system-high 88 times in 2018 — major hits or otherwise — and 48 times so far this year, putting it in second-place behind the N, which saw 52 incidents.

“They’ve been going into the yard tagging trains since I was a kid,” said a security guard at the Fresh Pond Yard, the Queens site where M trains are kept while out of service. “Years!”

Subway cars are often seen as the Holy Grail, in part because they can be tougher to reach in train yards due to normally staunch security.

But sources say graffitists are drawn to the Fresh Pond Yard by relatively easy access through the rear of a nearby tire shop.

When they do catch the taggers in the act, cops are often surprised to find that their identities defy their preconceived notions of vandals.

“He had nicer boots than I do,” said one NYPD source of an adult artist he busted in the Fresh Pond Yard. “You would think he was driven like a dope addict, the way he talked.

“He said when he sees his tag, he gets a rush.”

The MTA declined comment.

Additional reporting by Anabel Sosa