Birth rates and death rates are only loosely correlated. The drivers for each are different, so the numbers can at times have significant divergence. For example, Albania reports a death rate of 5.7 but a birthrate of 24.7. Both of these figures our outliers for the Eastern Europe group, giving Albania a very large spread compared with the other nations, and figures more akin to a developing nation.

There is a much stronger correlation between both birth rates and death rates and GNP. Nations with a low GNP tend to have higher figures for both birth and death rates. Those with a high GNP will tend to have lower birth and death rates. GNP contributes to death rates in a couple of ways. One is that wealthier nations tend to have better access to health care and clean water. As well, wealthier nations tend not to be as involved in conflict, the U.S. excepted, something that results in lower death rates. One set of outliers are the North African nations, which have lower death rates than their sub-Saharan peers. This can stem from better access to food and underground water sources, in addition to the historical medical knowledge passed down from ancient and Islamic sources, neither of which have the same influence south of the Sahara.

Birth rates are affected by GNP differently. People in wealthier nations have better access to family planning, but more importantly they have retirement funds and pensions. This means they need fewer children to provide for them in old age. Old age care is one of the key drivers for parents to have many children, in particular in countries with high death rates and low life expectancies (meaning not all of the children will survive long enough to take care of their parents).

4. Populations in the least developed countries are growing rapidly. The population growth can...

For example, Canada is a slow growing country, with a birth rate of 14. 5 and a death rate of 7.3, whereas many African countries have high growth rates based on birth rates in the 40s and death rates in the 20s.
If a nation's population grows at 2% per year, this represents rapid growth. The population will increase 21.8% after ten years and 48.5% within a generation. Doubling the population would take 35 years. This growth rate is fairly robust in the context of human history and is entirely unsustainable. Most populations did not historically grow at current rates. We have dramatically lowered death rates in the past century, but in many parts of the world birth rates have not yet fallen to match this.

As a result, the world's population is growing quickly. The areas exhibiting relatively slow growth amount to only a fraction of the world's population. The areas with faster growth amount to a large portion of the world's population, so the actual world growth rate is much higher than 2%.

Economic development directly correlates with positive results for people. In more economically developed nations, death rates are lower, and birth rates tend to fall as well. Population growth is robust in poor countries. Therefore to stem the current trend of unsustainable population growth, we must bring more people into economic prosperity. Life expectancies increase both for men and for women in developed nations as well, as result of improved sanitation and medical care.

Works Cited:

Rosenberg, M. (2007). Life expectancy. About.com. Retrieved November 11, 2009 from http://geography.about.com/od/populationgeography/a/lifeexpectancy.htm

Annual Register 1992 and UNESCO 1990 Demographic Year Book.