Maybe this is just a coincidence but I am lately getting a lot of US coinage in CWR (both pennies and nickels).
On my last trip to a bank I got ten rolls of nickels. Every roll had only one or two Canadian nickels on the ends of the rolls and the rest were all US (they are thicker so you can fill a roll with only about 36 nickels instead of 40).
No buffalos, no war nickels, oldest was '41, plus two late 40s and five from the 50's.
The last batch of pennies ran about 60% US (of which a pretty good number were Cu--over 30%).