Le Big Mac

I read in today's Le Monde, of all places, that it is the 40th birthday of McDonald's Big Mac (image by Andy Flesses). The original recipe was stirred up (ar ar) by Jim Delligati for his Pennsylvania franchise and is now part of the cultural heritage of America (hear the French snigger). Today, a Big Mac is sold in 30,000 restaurants in 100 countries - none of which have gone to war with each other. The Economist magazine, famously, began using the Mac as a price index between cities: the average in the USA is $2.69 compared to $4.17 in Europe and $1.45 in China. We went just the other day, where the sandwich sold for £1.94 or about $4.00 49% more dear than America. What's up with that, Ronald?