The loonie closed down 0.31 of a cent at 90.34 cents US after posting gains earlier in the day.
The latest retail data showed that Canadians shopped less in July, with sales falling an unexpected 0.1 per cent after six consecutive months of increases. The drop was even bigger after auto sales were excluded, down 0.6 per cent compared with June.
Economists had expected an overall gain of 0.5 per cent and flat results excluding auto sales, according to Thomson Reuters.
Overseas, data released overnight showed that despite a number of stimulus measures by the European Central Bank, the economy of the 18-country eurozone may be failing to gain renewed momentum.
In its monthly survey, financial information company Markit said its purchasing managers' index for the eurozone — a closely watched gauge of business activity — fell to a nine-month low of 52.3 in September from the previous month's 52.5.
It blamed the crisis in Ukraine, sanctions between the West and Russia and a general sense of pessimism about the eurozone's economic plight. Although anything above 50 indicates expansion, Markit said the improvement was due largely to Germany, Europe's largest economy.
"The survey paints a picture of ongoing malaise," said Markit's chief economist, Chris Williamson. "The danger is that the ECB's efforts to stimulate the economy will prove ineffective in the face of such headwinds, which are exacerbating already-weak demand."
Meanwhile, the news from China was better than expected.
HSBC's latest purchasing manager index edged up to 50.5 this month from 50.2 in August based on a 100-point scale on which numbers below 50 indicate contraction. Analysts had been expecting the reading to fall for a second month, pushed down by China's housing market. Still, August's PMI reading was a sharp decline from the 18-month high of 51.7 in July.
December gold was up $4.10 to US$1,222 an ounce, while the November crude contract rose 69 cents to US$91.56 a barrel. December copper was unchanged at US$3.04 a pound.
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