The average national price of petrol fell by 2.2 cents last week but rose slightly in Perth, according to the Australian Institute of Petroleum.
Over the past fortnight petrol prices have fallen by 4.9 cents a litre nationally.
CommSec Economist Savanth Sebastian said this is the biggest fortnightly fall in 21 months.
While the price at the bowser dropped in Sydney (down 3.6 cents) Melbourne (down 4.5 cents), Brisbane (down 2.9 cents), Adelaide (down 2.0 cents), Darwin (down 0.1 cent), Canberra (down 3.0 cents) it rose ever so slightly in Perth up 0.4 cents.
The national average remained at an eight-month low of 114.5 cents.
Mr Sebastian said motorists certainly have a lot to celebrate.
"In fact the magical $1 a litre could appear on signboards this week - especially given the recent strength of the Australian dollar," he said.
He said that looking forward motorists had little to fear.
"The terminal gate price is holding the lowest level since late 2009 and the cheaper wholesale price for fuel has ensured that petrol stations can afford to be more competitive," said Mr Sebastian.
