Here is some very rudimentary analysis of the effect of the price of oil (known as POO in the financial markets) on the pump price of petrol. Base data sourced from various web sites. Calculations are my own.
A barrel of oil contains 42 US gals (160 Lt)
The production from a barrel varies slightly depending on the type of oil and where refining is done, but the following is typical:
74 Lt petrol
35 Lt diesel
15.5 Lt jet fuel
41.5 Lt other products (kerosene, lubricants. asphalt, liquified gas, etc)
Total output (166 Lt) is a little higher than input (160 Lt) due to the addition of small amounts of various chemicals during production stages.
Lets assume that the only thing to vary over a period of time is the POO. All other production costs remain unchanged.
44.5% of output is petrol
21.1 % of output is diesel
For each $10 increase in the price POO, $4.45 should flow through to petrol, with 6 cents attributed to each Lt of petrol produced
For each $10 increase in the POO, $2.11 should flow through to diesel, with 6 cents 6 cents attributed to each Lt of diesel produced.
Over the last year or so, crude oil has increased in price by about $30 (from $30 - $35 up to $60 - $65).
So over that time, any increase in the retail price of petrol and diesel above 18 cents is the result of something other than the price of oil. Without research, my guess is that the retail price has gone up by 30 to 40 cents in that time. Why the difference?
The biggest factor would be tax (the higher the oil price, the greater the tax take; hence the governments reluctance to take any action). Not sure at the moment how much this would be per Lt.
Another factor would be distribution costs (driven up by the price of petrol and diesel). This should not be more than 1 cent per Lt.
By my reckoning, pretty much everything else would be increased profits in the supply chain; oil companies, wholesalers (where they exist) and retailers.
My only conclusion is that only about half (perhaps less) of the increase in the retail price of fuel can be directly attributed to the price of oil. The rest is other factors, including tax and probably increased profits.
Make your own conclusion, but that is
mine.