Charter school enrollment is continuing to tick upward in cities across the country. And in 208 districts, at least 10 percent of public-school students attended a charter last school year.

That’s according to the annual analysis from the National Alliance for Public Charter Schools, an advocacy group that tracks the sector of publicly funded, privately run schools. The year before, 190 districts had reached that 10 percent threshold.

It’s a trend line with profound implications for school districts — which often have to reshape themselves as local charter sectors grow, keeping students and funding outside of their purview — as well as teachers unions and families.

Other milestones the report notes for 2015-16: New York City’s charter enrollment hit 100,000 students, and Denver’s charter enrollment share hit 20 percent.

Here are two handy charts for tracking the schools’ growth. First, the districts with the largest share of students attending charters:

And second, the districts with the largest total number of students attending charters:

You can read the whole 2017 report here, or compare to last year’s here.