Two of the biggest shopping days of the year are still weeks away, but many Canadians already plan to call in sick in order to hit stores -- and keyboards -– in order to spend, spend, spend.

Few people can resist a good deal and Canadians with a healthy dose of “shopping fever” will spend more than $13.4 billion over Black Friday and Cyber Monday according to a new study by IPG Mediabrands.

Black Friday, the big retail sales day the falls the Friday after American Thanksgiving, and Cyber Monday, the online bargain event that comes the Monday after, were invented by retailers primarily for U.S. shoppers.

But according to IPG Marketing Manager Loraine Cordery, the two shopping deal days -- which fall on Nov. 28 and Dec. 1 this year -- have become a big deal for thrifty Canadians, too. And retailers are only too happy to oblige.

Cordery says a growing throng of Canadians have joined the early storefront lineups and stampeding crowds or are hovering over their computers looking for bargains.

“Forty-nine per cent of Canadians will participate in Black Friday, Cyber Monday or both -- so there’s a lot of spending coming up,” Cordery told CTV News Channel. “Everyone loves a good deal.”

But according to the IPG study, a lot of that shopping will be done on company time, as millions of Canadians plan to call in sick, take a vacation day or use their computer at work to take advantage of deals.

Here’s an IPG tally of the Black Friday/Cyber Monday impact on Canada:

• 965,000 people will call in sick from work

• 4.1 million will take a vacation day

• 2.3 million plan to shop during work hours

“It may feel more like Slack Friday to many employers,” IPG Mediabrands Vice-President Chris Herlihey declared in a press release. "Clearly, Canadians are planning ahead and making time for what is fast becoming the most popular shopping weekend of the year."

The IPG report suggests that Canadian retailers need to do more to embrace the trend or lose out on valuable sales.

According to the study, 24 per cent of Canadian Black Friday shoppers will cross the border and spend $1.6 billion buying up stateside deals. And Canadians will spend up to $3.4 billion on U.S. websites on Cyber Monday.