So pretty much all measures or indexes are inaccurate in that light. The reason I like it is that it takes a product that’s priced proportionally to local labou

So pretty much all measures or indexes are inaccurate in that light. The reason I like it is that it takes a product that’s priced proportionally to local labour and commodities, is globally recognisable and serves as an easy frame of reference. For products and services that have near zero marginal costs. Saying something is worth 2 cups of coffee, for instance, is useful but our coffee prices might differ by an order of magnitude. But McD is always a middle class lunch wherever they run. The other alternative I can think of is Coca Cola. That would also be an interesting index.