Most cryptocurrencies are subject to this volatility, except stable coins.
Amongst those volatile, dogecoin is relatively stable for long periods of time, so also Tron, as far as I know.
stable coins like usdt keep a constant 1 : 1 price to USD and rarely fluctuate in price, even when they do fluctuate it's by a very very small amount usually less than 1 cent or so.I do agree with you that dogecoin remains stable for a long periods of time. However, even its value changes slighty. I did some research and found that Thether (USDT) is the least volatile and its value has remained stable for a very long peiod of time.