Angola’s oil production rose 6 percent year-on-year in 2015, to over 649 million barrels, the country’s state-owned energy firm Sonangol said last week.

Sonangol produced approximately 1.779 million barrels a day in 2015, the firm added in a statement.

Natural gas production in the African nation fell 8 percent year-on-year to 507,000 tonnes last year, the company said.

Despite a growth in oil production, Sonangol posted a 34-percent decline in revenues, to 2.29 trillion kwanzas (US$14.38 billion), last year. The deterioration was attributed mainly to falling oil prices. The country’s currency receded 35 percent in value in 2015 against the U.S. dollar according to Agence France-Presse.

Sonangol’s net profit plunged 68 percent year-on-year in 2015, to approximately 44.15 billion kwanzas, the firm said.