According to a report by the Energy International Administration, the statistical arm of the United States’ Energy Department, Nigeria’s crude oil production is expected to remain depressed through 2017 as a result of militant attacks, Punch reported.

In May 2016, disruption to crude oil output in Nigeria reached 750,000 bpd, due to attacks on oil and natural gas facilities, with production halts concentrated in the Niger Delta region (NDA), an oil-rich area bordering the Gulf of Guinea that is the mainstay of the country’s crude oil production.

Attacks have also impacted Nigeria’s exports of multiple crude oil grades, including Bonny Light, Forcados, Brass River, and Qua Iboe. Export agreements have been under periods of force majeure since the beginning of 2016, according to Today in Energy.

Nigeria, a member of the Organization of the Petroleum Exporting Countries, was considered Africa’s largest oil producer until Angola overtook it in 2015, with the country’s production falling from 1.9m b/d to 1.4m b/d in May 2016, nearly a 30-year low.

The disruptions in oil production, combined with relatively low crude oil prices, have had a significant effect on Nigeria’s economy as the oil sector provides 70% of government revenue and 95% of export revenue.