I guess it's not a secret anymore that position sizing is pretty crucial to what we do. How do you calculate the position size for each trade on the fly? Note - I am not after the 2% risk or how to mathematically calculate position size based on that. My question relates more to time aspect and how to at least approximate the position size in real-time.
I have written myself a little spreadsheet where I enter account size, price, SL & TP and it calculates things for me. Problem is that even trading in the 5min chart this takes too long and needs to be adjusted all the time. Is there a better solution out there?