Reports of so-called “non-index” crime on the CTA in Chicago are on pace this year to surpass each of the past two years, including the number of cases of “criminal sexual abuse” such as “inappropriate touching” and “sexual harassment without physical contact.”

There have been 145 instances of criminal sexual abuse reported on the CTA in Chicago since the beginning of 2015, with the number of such incidents rising from 44 in 2015 to 60 in 2017 as of Oct. 27.

That’s according to a Chicago Sun-Times analysis of Chicago Police Department data on “non-index” crimes — those regarded as less severe than “index” crimes such as murder, robbery and rape.

The L system, in particular, has seen an uptick in those sex crimes, which can be classified as either a misdemeanor or felony.

There have been 2,003 reports of non-index crimes on the CTA in Chicago in 2017 through late October, ranging from fights to gambling, drug use to vandalism.

By comparison, there were 2,006 such reports for all of 2016 and 2,036 the year before.

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The Sun-Times analysis also found:

• Nearly half the petty crime this year on the CTA in Chicago was reported on L trains and inside L and subway stations, followed by buses, train platforms, bus stops, parking facilities and track areas.

• That’s in contrast to the past two years, when most of these relatively minor crimes on CTA property were logged on buses, with 499 such reports in 2015 and 480 last year.

• The police don’t have a solid handle on the number of arrests that have been made in these cases — though more than half of them haven’t been solved.

• Simple battery — which can be a slap or a fistfight — is among the most prevalent of these crimes, with 721 such reports on the CTA in the city in 2015, 750 in 2016 and 629 this year.

• Vandalism reports are up, with 429 so far this year, up from 302 in 2016 and 348 in 2015.

The findings follow a Sun-Times report in July that found that more serious CTA-related crime was up 16 percent in Chicago in 2016. The newspaper also found then that the police solve fewer than 10 percent of those cases in the city and that the CTA doesn’t track any type of crime — purposely, according to a transit source who said the agency was loath to make the system look dangerous — in the dozens of suburbs where it operates.

Neither CTA President Dorval Carter Jr., who reports to Mayor Rahm Emanuel, nor CTA security chief Pat Daly, a former FBI agent, responded to requests for comment.

The police said the department’s transit unit “works in close partnership with the CTA to ensure that riders can travel across the city with peace of mind. Although non-index crime levels have remained within a consistent range for the last several years, including 2017, CPD has increasingly utilized data to analyze where upticks occur in order to increase attention in those locations.”

CTA spokesman Steve Mayberry said the crime figures show for the past two years that “only one petty crime was committed for about every 250,000 rides taken in CTA’s system. These numbers reflect the fact that petty crime on CTA is very low and that we are largely successful in our ongoing efforts to ensure that most people get to work, school and elsewhere without incident.”

But problems on the CTA often go unreported, according to interviews with riders.

“A lot of times people just get off the train,” said 27-year-old Kyle Goethals.

An Old Town resident for the past five years, Goethals takes the train to work at an ad agency in the West Loop. Though he’s seen people drink alcohol, relieve themselves and smoke what appeared to be marijuana on CTA property, he said he doesn’t report any of that.

“It’s easier to just change cars,” Goethals said at the Green Line L’s Morgan station. “If you’re like me, you don’t have a car, but you still need to get to work. So I think people are more likely just to . . . deal with the immediate problem, which is, ‘I don’t want to be next to something like this,’ and less likely to take the extra step to make a call.”

Edgewater resident Qiara Tate, 24, said she’s used public transportation her entire life. She said she has seen people peeing and harassing others on CTA property but hasn’t reported any of the incidents.

“That stuff always happens,” Tate said. “I see it everywhere — vandalism, graffiti, going to the bathroom. But it’s always been like that.”