I think Scotland and other countries have been victims of mass manipulation.
For some reason OPEC have never managed to agree to cease oil production, which would stabilise the price.
In the USA they are importing cheap oil, as much as they like, while, as a bonus, are getting to close down some of their fracking companies.
The low cost per barrel is detrimental to Russia, which is a plus for the USA and UK Governments, as Russia have stopped using the dollar when buying and selling oil.
The low cost per barrel also means the UK Government get to say, "Ha ha, I told you so!", to the Scottish Government - the SNP, regarding Scottish Independence . They also allege that it ruins the argument regarding Full Fiscal Autonomy. Sigh! Scotland is the only country where having oil is a burden.
Then while reading about a particular company over in the Middle East , I believe the Director's are a Rothschild, a satellite TV company owner and an ex US Vice President - it crossed my mind that they were buying the oil off of them folks in Syria and Iraq, selling it on for cheap while still making a hefty profit, thus contributing to the low cost of a barrel.
Everyone's a winner - well, the 1% are, and that seems to be all that matters.