A Google search for "Germany population" brings up this graph. Population of Germany

A spike around the year 1989 is clearly visible. What can cause such a spike in population? Is it something related to the census system, is it a fault somewhere in Google's database or did the population really increase that quickly in 1989 in Germany? If it did, what could be the reason behind it?

closed as off-topic by Giter, Brasidas, Santiago, sempaiscuba Feb 7 at 14:46

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