There are 567,000 fewer educators in U.S. public schools than before the pandemic, with the ratio of people hired to job openings in education at an all-time low this school year, and it’s worse in the poorer school districts.

For each vacant position, there are 0.57 hires, according to the National Education Association, the largest U.S. union representing nearly 3 million educators.

The teacher shortage isn’t affecting all schools equally. Students in the poorest school districts are being hit hardest because schools are funded with property taxes. Several teachers told TIME they were leaving their school district for other districts that pay more and offer more resources. At least one survey found that schools in lower-income areas are more likely to have vacancies.

The massive staff shortages are leaving educators increasingly burned out, with 55 percent of respondents in a recent survey saying they are ready to leave the profession sooner than planned.

“This is a five-alarm crisis,” said NEA President Becky Pringle in a press release.

Big red flag: K-12 education lost more than 21,000 workers in September.

Public education remains one of the least recovered industries from the pandemic.

**There are 309,000 fewer teachers and support staff than pre-pandemic** pic.twitter.com/XadWUERu3X

— Heather Long (@byHeatherLong) October 7, 2022

Schools with more Black students and those in high-poverty neighborhoods report a larger percentage of teacher vacancies than schools serving mostly white students and schools in wealthier areas, according to a January Education Department survey. But that was happening before the pandemic too.

The teacher shortage problem varies widely by state, according to a working paper published in August by the Brown University Annenberg Institute. Mississippi, for example, has about 68 vacancies per 10,000 students. New Jersey, home to some of the wealthiest communities, had one vacancy per 10,000 students for the 2021-2022 school year.

A new state law allows New Jersey school districts to temporarily hire retired teachers to fill vacant classroom jobs and it’s having a big impact in Newark, NJ.com reported. Retirees are being paid $92,000 for the 2022-2023 school year while continuing to receive their pensions, district officials said.

The school district also raised the starting salary of permanent teachers from $55,469 to $62,000, citing staffing shortages.

“Teachers are in a very good place right now to negotiate salaries,” said Yolanda Méndez, Newark assistant superintendent.

As schools struggle to find educators, some no longer require college degrees to fill teaching jobs full time. Public officials are openly challenging the idea that a degree in education should be a prerequisite for getting into the classroom and hope to undo longstanding license rules, Washington Post reported. 

Many states increasingly rely on substitutes, who are usually not required to have college degrees — to fill teaching jobs full-time.