$1.50 per litre is $5.70 per US gallon. According to the AAA, today's US average is $2.25, making gas in Sweden 2.5x as expensive. I think GP's point stands, even if the numbers were a little off.

For the record, gas prices in Germany are similar to Sweden, maybe a couple of cents lower (currently around 1.35€ per litre—around 2.35 times the US average)

Sorry, I wasn't aware that the dollar has increased so much in value..