First, there are a few things I'm not clear about, like what the 'risk free' return is.. is there even such a thing in trading? or how to handle inactive days, etc. Let's assume I have a period of 30 days. During these 30 days, I have 5 trades with their duration: +5%, 2 days -3%, 5 days +1%, 3 days +2%, 1 day -2%, 3 days I have 16 days where there is no activity. How would I calculate the Sharpe ratio from these values? I see a lot of questions on the topic, but I'm looking for a down-to-earth