In the long run—think centuries—the world faces the opposite problem. The United Nations (See "World Population to 2300," Economic and Social Affairs/Population Division, UN) make long-range population projections. According to their demographic specialists, the world faces a demographic winter instead of a population explosion. Population grows and declines arithmetically. For example, if the replacement rate is 2.1 persons per couple then with a rate of 1.0 the population would halve in a generation. As a result, places like Singapore and Russia with already very low birth replacement rates can expect to disappear as nations in the coming centuries, especially Russia. Russia also has a high alcoholic death rate and a few years ago the average Russian woman had 5 abortions if a guest on a Bill Moyers' PBS program is to be believed. Alarmists predict packs of wolves roaming in deserted Western and Eastern European cities in a couple of centuries.