The tumbling fuel prices, which have also seen unleaded fuel drop to €1.13 a litre, has been attributed to falling oil prices which are currently bordering on a seven-year low.
This week, a barrel of Brent crude was trading at US$41, with oil producers said to be bracing for further plunges in coming weeks which could see the cost per barrel fall to as low
as $20.
Oil producers had last week tried to broker a deal to push the price of crude up, but a group led by Saudi Arabia last week failed to agree measures to restrict supply, which has had the effect of pushing prices back up.
This time last year, a barrel cost $65 and back in June 2014 it stood at $115.
The dropping fuel prices have also been explained due to the euro strengthening against the dollar, following stimulus measures introduced by the European Central Bank to aid the ailing single currency.
But despite Portugal seeing petrol prices drop to figures last seen in the previous decade, the country’s prices remain high in comparison with other European Union member states.
Diesel is currently the 11th most expensive in the 28-state union, while petrol is 10th on the list.
The United Kingdom tops the list, where unleaded petrol costs an average of €1.46 a litre, while diesel costs just under €1.50. However, the strong sterling has helped to push the UK to the top of the list, as before conversion, petrol currently costs little more than a pound a litre.
At the bottom of the list is Saudi Arabia, where petrol costs 11 cents a litre, while in the United States, fuel costs 47 cents a litre.
Despite these latest series in drops of fuel prices, which are expected to continue well into the festive period, Portugal’s retailers have come under criticism for not reflecting plummeting oil prices at forecourts, but are quick to react when costs rise.
But according to the Portuguese Association of Fuel Companies (Apetro) the fact that these savings have not been passed on to consumers is largely due to the high taxes levied on fuel at the pumps along with the fixed costs that fuel stations have to absorb.
Currently, around 60 percent of the cost of a litre of unleaded fuel is paid over to the taxman, while half of the cost of diesel is channelled to the state’s coffers.
Fuel companies allocate a further 11 percent of the cost of fuel towards storage costs, which according to Apetro, leaves petrol stations with little room for manoeuvre - even as the price of oil continues its downward spiral.