That's how much they're going up? Or how much they will be? I have no idea, I rarely buy any, but I did just run out yesterday With the P.O. going broke I wouldn't be suprised to see that kind of increase.
A few years ago Canada stopped putting the price on the actual stamps and if the price goes up we are allowed to use the old ones.
I have a few booklets saved up and it's nice to not have to keep track of postage or buy extra 1c and 2c stamps to make up the difference if it does go up
We have forever stamps, though I think you have to request them from most PO's. We just throw an envelope in the mail box without a stamp. When the change in the box gets a little low, we throw a pocketful of change in there. We're awful!