Around 1000 percent profit since March last year. 80 percent plus in December alone. The Bitcoin course has not stopped for weeks. He jumped over $ 40,000 late last week, almost exactly four years after breaking the $ 1,000 hurdle. But on Monday it went down again by 20 percent, and on Tuesday ten percent up. Savers and investors are stunned by this development and wonder whether they should jump up now. And behind this is ultimately the question of what the true, fair value of a Bitcoin actually is, and where it can develop.