And coins percentage most likely change depending on the current market situation.
No there is no specific amount or percentage of holding coins. I believe that every trader has their own strategy or ways on which they think they will benefit more. The percentage or the amount will definitely depend on the owner. As a newbie trader, I often more than half of possible profit due to bad decision making. Sometimes, the price of the tokens will suddenly go down and it was also the time when I needed some money so what would happen is that I will be forced to trade at low prices because I need to.