Oil prices, today at $78 a barrel, have fallen from a high of over $115 earlier this year, creating difficulties for a number of producer countries. OPEC will meet tomorrow in Vienna to agree production quotas for its members.

Here are 4 things you need to know about tomorrow’s OPEC meeting.

1. Oil producers are struggling to break even

 According to Thomson Reuters, prices are now so low that a number of major oil producers will be running fiscal deficits this year: for example, Nigeria needs an oil price of $126 to balance its budget, Iran $130 and Venezuela $162.

2. Will oil prices rebound back to over $80?

The FT reports analysis from Deutsche Bank predicting that OPEC will cut production by 1 million barrels per day, raising oil prices by 8.5% to around $87 a barrel by February 2015.

3. Are falling prices a Saudi plot to bankrupt Russia?

The big question is whether the Saudis will continue to maintain high production levels as part of its mooted geopolitical battle with Russia, a theme that Neil Barnett recently addressed for CapX. Russia needs an oil price of at least $100 a barrel to balance its budget.

4. Could oil prices fall even further, to below $60 a barrel?

Analysts at Zero Hedge suggest that the combination of weak demand, declining influence of OPEC on global markets and the US shale gas revolution could push prices down to as low as $60 a barrel. There are doubts within financial markets surrounding OPEC’s credibility to enforce quotas and the role of non-members – Russia, Mexico and Norway – in driving supply.