DES MOINES, Iowa (KCCI) — Iowa’s new private school scholarship program will cost the state millions of dollars more than the original estimate. As of October, 16,757 students were using taxpayer dollars to pay for private school tuition and other academic resources. That’s about 3,000 more than they expected.

Since each student receives their own Education Savings Account with more than $7,500, the ESA program will cost the state $127,939,695. That’s $20 million more than the $107 million the state projected this would cost. The governor’s office says that additional money will come from the general fund, which is all of the state’s available revenue from things like income, corporate and sales taxes.

School funding in Iowa is based on a complicated formula, but it relies on certified enrollment totals, which give the state a baseline of how many students are attending Iowa schools. The numbers determine how much the state will spend on education in the next school year. It also gives state lawmakers — who are currently in legislative session — a benchmark on which to base laws and funding.