From Strategy Page:
We recently updated the Armed Forces of the World database. The regional charts there give evaluations of the quantity and quality of each nation's armed forces in that region. The quantity of each combat unit has been derived from various open sources. Quality has been determined by evaluating historical performance. All armed forces are not equal, and this inequality has been expressed numerically. In calculating the numerical value of total strength it is important to differentiate between what floats and what doesn't. Aircraft carriers and tank divisions are very different instruments of destruction. Both cost about the same, but a carrier cannot march on Moscow, nor can a tank division hunt submarines in the Atlantic. For this reason, land force capabilities only are listed. In reality, they are not entirely separate. Naval forces, particularly carriers, can support ground combat. Tank divisions can seize ports needed by naval forces for their sustenance. Destructive effect was the main consideration in assigning values. This was modified by the mobility and flexibility of the system. Tank divisions can move over a wide area to fight while most air defense forces are limited in their capabilities and mobility. While the numbers of men and weapons are fairly accurate, estimates of quality factors are subjective. Readers may impose their own evaluations. The assessments given are based on current conditions and historical experience. Don't underestimate the historical trends.
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