I did some calculations in Excel, using independence dates provided on About.com, and found the average age of a country is about 158.78 years old. Now, before anyone throws a tizzy about what makes a country a country, about nations, tribes, civilizations, ethnic categories, or about my makeshift methodology, keep in mind, I simply assessed 195 countries based on their political sovereignty. That is the occasion we're celebrating today, right? Try this map."
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