Burgernomics, complete waste of time.
I had a colleague moving from one country to another (less expensive to much more expensive) and someone tried to justify his salary change as the change in ratio of Big Macs.
I guess thats great if you eat Big Macs morning, noon , and night. And if your landlord will let you pay your rent in Big Macs.
Personally, why only the Big Mac? I always have the meal deal so shouldn't we at least move to that more reliable indicator

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In my colleagues case rent costs were easily double.