The Canadian dollar hit a new milestone Thursday, trading above $1.04 US for the first time in 33 years.

The loonie reached a high of $1.0403 US in intraday trading, according to figures from the Bank of Canada. That's its highest level since May 27, 1974, and only 2.11 cents below the loonie's postwar high of $1.0614 US, set back on Aug. 21, 1957.

The Canadian dollar has risen 21 per cent against the U.S. greenback since the start of the year. Since early 2002, the rise has been a stunning 67 per cent.
(Canadian Press/Ryan Remiorz)

The dollar later slipped back to close at $1.0353 US, up about a third of a cent from Wednesday.

Analysts said the soaring price for oil and the sinking worth of the U.S. dollar on foreign exchange markets were again the key factors behind the loonie's move up.

Crude oil futures closed at a record high above $90 US a barrel on Thursday on word that OPEC production increases aren't coming as fast as had been expected. That led to more worries about supply.

The U.S. greenback also had another bad day. Bloomberg said it weakened against all 16 of the most frequently traded world currencies.

So far this year, the loonie has appreciated by almost 21 per cent against the U.S. dollar. Five weeks ago, it reached parity with the U.S. currency for the first time since 1976.