What we know we don't know: No one knows who exactly lives in Lebanon. The country hasn't held a census since the French colonial government conducted one in 1932.
Why we don't know it: A census would likely reveal the uncomfortable truth -- for Lebanon's Maronite Christians -- that their numbers have been slipping as a percentage of the population. When Lebanon became independent in 1943, a national pact divided power between Christians and Muslims on a 6-5 ratio based on the 1932 census, later changed to an even split after the country's brutal 1975-1990 civil war. Since then, the Shiite Muslim community is believed to have grown faster than any other group, but Christians, despite making up only an estimated quarter of the population, still hold half the parliamentary seats. They'd prefer to keep it that way.
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