Mexican educators are being promised retroactive raises.

To address what federal officials call inequities in pay for the country’s hundreds of thousands of educators, Mexico will spend some $1.2 billion on those raises.

On top of an across the board 3.5% salary increase and a 1.8% increase in benefits, educators making less than 20,000 pesos — or roughly $1,000 — a month, will receive additional staggered raises of 1% to 3%, with the biggest jump going to the lowest earners, according to Treasury Secretary Rogelio Ramirez de la O.

The raises will be retroactive to the first of the year.