Sorry to disagree but Bitcoin is much riskier than any investments because the price is really unpredictable unlike the bank notes that it guarantee the earnings except if the bank will be bankrupt but we could choose the best banks to prevent this bank notes of loosing. Bitcoin is better than bank notes in talking of earning but that was just only if the price of Bitcoin keeps on increasing but if the price fall down like from $19,800 to $8,000 then that is another story.