The currency was down 0.35 of a cent to 96.81 cents US, its lowest close since Dec. 19.
Weak economic data from Canada's biggest trading partner often has a negative effect on the loonie since it signals lower demand for commodities such as oil and metals and manufactured goods.
The month of May has been a tough one for the Canadian currency.
It has tumbled 4.63 cents US as worries about the future of the eurozone have resulted in traders avoiding riskier assets such as equities, commodities and resource-based currencies such as the Canadian dollar.
Instead, traders have flocked to the safe heaven status of U.S. Treasuries.
Employment firm ADP said the U.S. private sector created just 133,000 jobs this month, less than the 150,000 that economists had expected.
Economists have been expecting that the U.S. government's non-farm payrolls report being released on Friday will show the American economy cranked out about 140,000 jobs in May.
Meanwhile, the number of Americans filing for jobless insurance last week came in higher than expected — 383,000 versus 370,000.
Also, first-quarter U.S. gross domestic product growth was revised downward to 1.9 per cent from 2.2 per cent, which was in line with expectations.
The commodity-sensitive currency was hit by another day of sliding prices for oil and metals.
The July crude contract on the New York Mercantile Exchange lost $1.29 to US$86.53 a barrel, its lowest level since October. Crude has tumbled 17 per cent this month.
The June bullion contract on the Nymex edged 20 cents lower to US$1,564 an ounce. Copper extended Wednesday's seven-cent slide, down two cents at US$3.37 a pound.
The head of the European Central Bank has warned, in response to questions from the European Parliament, that the 17-country euro currency union is unsustainable.
ECB head Mario Draghi said Thursday that the crisis had exposed the inadequacy of the financial and economic framework set up for the euro monetary union.
Greece has been at the centre of worry about the eurozone, particularly after inconclusive elections May 6 saw increased support for parties dead set against the austerity measures that have allowed the country to keep afloat on massive international bailouts. Uncertainty over Greece will rattle markets at least until the next Greek election June 17.
But Spain’s banking system has also been under close scrutiny, especially after Bankia, the country’s fourth-largest lender, last week announced it needed €19 billion in state aid.
Investors are worried that Bankia’s woes might be replicated across Spain’s banking sector, which has suffered badly from the collapse of the construction sector. An economic recession has fuelled concern that the country will become the fourth euro country to be bailed out.
Nervous traders have sent the yield, or interest rate, on Spain’s 10-year bond to around the 6.5 per cent mark, and not far from the seven per cent threshold that is considered to be unsustainable in the long-run.
There was some positive European economic data to digest.
Inflation across the 17 countries that use the euro fell by more than anticipated in May, a development that will likely add pressure on the European Central Bank to cut interest rates next week to help the struggling eurozone economy.
Eurostat, the European Union’s statistics office, said annual consumer price increases slowed to a 15-month low of 2.4 per cent in May from 2.6 per cent the previous month.
And in Germany, Europe's biggest economy, retail sales rose a solid 0.6 per cent in April, tripling expectations.
On the Canadian economic front, the country’s current account deficit came in at $10.3 billion in the first quarter, up $600 million from the prior quarter.
However, that quarterly change had already been signalled by a deterioration in the trade balance for the quarter, observed a commentary from CIBC World Markets.Suggest a correction