Petrobras, Brazil’s state-owned oil company, has slashed its five-year investment plan and production forecasts as it seeks to adjust to a devastating corruption scandal and the fall in oil prices. Petrobras, which is one of the world’s most heavily indebted oil companies, said that it was cutting its projection for investment in 2015-2019 to $130.3bn, or by 37 per cent in relation to its previous plan.