You'll notice that prosperous, dynamic economies like the United States, Canada, Brazil and South Africa buy a lot of toilet paper, which would tend to correlate with a high number of bathrooms per capita. Countries in the developing world with very young populations, like Mexico and much of Southeast Asia, buy a lot of diapers and nappies (China, in particular, is likely to see a boom
in diaper consumption as it relaxes its one-child policy). Interestingly, feminine hygiene products sell best in Muslim countries like Iran and Pakistan. And those with low birth rates facing a wave of retirees, like Japan and much of Western Europe, mostly consume products for taking care of incontinence.