The consumer watchdog has found Australia's low petrol prices are also incredibly profitable for oil companies

Australian Competition and Consumer Commission’s (ACCC) regular look at the nation’s average petrol prices has found that in 2015–16 they were at their lowest levels since 2002.

That’s great news for motorists, but it turns out the oil companies have been enjoying them too, pushing gross retail margins to the highest level since monitoring began 14 years ago.

The consumer watchdog says their analysis shows that the industry is pocketing a substantial proportion of the drop in international crude oil and refined petrol prices rather than passing it on to motorists.

The average price for petrol in Australia’s five largest cities (Sydney, Melbourne, Brisbane, Adelaide and Perth) in 2015–16 was 121.7 cents per litre (cpl). That’s the lowest annual average since 2001–02 in real terms (adjusted for inflation).

But meanwhile, gross retail margins – the difference between retail and published wholesale prices – in the five largest cities increased by 1.2 cpl on the previous quarter, and averaged 11.2 cpl in 2015–16, the highest level since monitoring began in 2002.

The ACCC’s quarterly report found prices in the five largest cities in the June quarter 2016 were 118.0 cpl, an increase of 7.0 cpl from the previous quarter