The best and safest method to grow your bitcoin like a bank?

[bosshyip]

Hello guys, let's say we've already had some bitcoins in our wallets already. But the bitcoin in the wallet won't grow on its own.

Here "method to grow your bitcoin", I do not mean ways to earn free bitcoins, and I do not mean those known methods like Bitcoin Faucet, Bitcoin Mining, Bitcoin Trading, Bitcoin Gambling, Bitcoin lending either, because these methods are not safe at all, we may most probably lost our bitcoin rather than grow.

I am wondering is there a reliable and safe method to grow bitcoin day after day by getting interest like we deposit fiat to a bank and the bank pay us interest?