Tax revenue, including Value Added Tax (VAT), amounted to 5.5 per cent of the total public revenue in 2018.
That's according to the Ministry of Finance (MoF), which said oil revenues added 36.1 per cent, while profits of public joint-stock companies accounted for 32.9 per cent.
It added that 2018 witnessed a budget surplus of 2.2 per cent compared to a 0.2 per cent deficit the previous year.
The federal government introduced 5% VAT at the start of 2018 to promote economic growth in isolation from oil revenues.