City schools are learning more about how their graduates fare in college. But parents aren’t getting the new reports, at least for now.

That’s because the city knows how only a small fraction of graduates perform in college and doesn’t want to suggest it has complete information about how well schools prepare their graduates.

A data-sharing agreement between the City University of New York and the Department of Education means the city knows more than it ever has about high school graduates enrolled at CUNY schools. But they make up only half of all college-bound graduates, who in turn represent just 60 percent of high school students.

The new reports explain whether graduates who enroll in CUNY colleges need to take remedial classes and whether they stay enrolled. But they don’t say anything about the 42 percent of graduates who go to private colleges and colleges outside of the city. And they also leave out the one-third of graduates who don’t go to college at all.

Without that information, the reports aren’t terribly useful for parents trying to figure out how well schools prepare students for college, and they could give inaccurate impressions of how well schools compare to each other, said Shael Polakow-Suransky, the deputy chancellor in charge of accountability.

“You could have really misleading information if you try to make a comparison [between schools], because there are variables missing,” he said.

Depending on the variables, the percentage of a high school’s graduates who need remedial courses at CUNY could have little to do with how the school is doing overall.

As an example, two high schools could be sending the same percentage of their alumni to remedial courses at CUNY. But comparing those schools might not be fair: one of those schools could be sending most of the rest of their students to top schools, while most of the other’s graduates could be entering the workforce directly. In the first school, it’s the weakest graduates who need extra help in college. In the second, it’s the very strongest.

Suransky said the reports can be useful to schools even if they aren’t likely to be meaningful to parents. ”We really want schools to start a conversation internally, and this information is a real wake-up call,” he said.

Principals are free to share the reports with curious parents if they want to, and Suransky said that the school’s administration can give parents a more complete picture of how the school’s graduates are doing. “They can contextualize it,” he said.

The city isn’t using these data reports to evaluate schools. But the city is planning to make college-readiness a factor for grading schools in its progress report system.

Suransky said that it’s not likely that CUNY remediation rates will count in the progress reports, but the city is still figuring out exactly how it will measure how well high schools prepare their students for college.

Here’s the city’s sample mock-up of the reports the city sent high school principals: