If you remember some of your economics, you will know PPP stands for Purchasising Power Parity. I personally would say, the term itself should be abolished. Power aside, there can never be parity as far as purchasing goes.

Otherwise, anything to do with Purchasing cannot have Parity.

Take this example (in Indian Rupees, of course).
This pair of leather boots I dig, are a cool 2,000. The lower end Nike/Reebok/Adidas shoes can be got for 2000+. The price of a local-make microwave oven is 2,700. The price of a DVD-MP3-anything player is 1,500 (branded).
The price of a sumptuous meal for two at a decent restaurant with drinks in a non veg joint can be 1,500+taxes. The price of one bottle of good Indian wine can be 1,000. The price of a pint bottle of Corona can be 500+taxes, so for two, it would be 1000+taxes and wont even have the same effect as 750 ml of Vodka.
The price of a pair of Nike shorts can be 1,300 (which I loved!). The price of renting a car for 800Km is 1000. The price of a Pink Floyd DVD is 699. The price of a broadband connection is 2,000 per month.
The price of the book you really want is at least 1,000. The charge for an all-India library membership is 1,000.
The price of a good perfume begins from 1,500. The price of a pair of jeans start at 1,200 (branded). The price of a gold&diamond pendant can begin from 2,000. The price of a jazzy artifical set of jewelry can be 2,000.

Your whole monthly grocery shopping can be completed in 2,000.

Where is the parity?

When I go out to buy that pair of jeans, which other thing should/ could I rather buy/ should buy with the same moolah? Is buying the CD really "worth" it? Is buying the book better than getting a library membership? We can think nothing of spending 2,000 on a dinner, or on a single small bottle of Johnny Walker, which would be over in the next hour. And think 10 times before spending it on that DVD player which would be outdated in a year.
I personally, would reason that since I hardly cook, Id rather buy a microwave later, and buy those pair of boots now which would last me till later. Now, would I? Or should I go and buy that book? Or simply, go get the membership? Or, add it all up and save money for my tax returns.

Where, is, the Parity? All hogwash I tell you! ^_^