One of my trading strategies is to enter stocks occasionally after hours; for instance SNAP this past week.   To enter I need three characteristics; I need to know the news or earnings info; I need to see the right type of after hours price action and I want to see a high % of daily volume traded after hrs; normally at least 20% before I'd take an entry.    Is it possible and if so can you give me some ideas on how to create an indicator that might display the after hrs volume % somewhere on the