Thank you for your comment. The numbers I used are from the most recent Nigeria Economic Report published by the World Bank, using National Bureau of Statistics data. 2012 real GDP was 2.7 times larger than in 2000 (see pages 9-10), which implies an annualized growth rate higher than 8%. Other data sources may give slightly different growth rates based on technical differences but the basic point will remain that Nigeria's reported GDP growth over the past decade has been high. The same report cites oil-derived revenue as 75% of the consolidated budgetary revenues.