Learn To Calculate The Profit Or Loss % Of A Share! Calculating the profit/loss % of a share you invested in could be a great way to keep track of your portfolios p&l (profit & loss). So, today I'll help you learn to calculate the Profit/Loss percentage on Investment with an easy formula. So, here we go; This is the formula & the steps.... The image above is the only thing you'll need to understand the formula; Let me cover the basics quickly; So the procedure of taking out the Profit/Loss % consists of 2 major steps; Step 1 is to first subtract the Cost Price (C.P.) from the Selling Price (S.P.) Cost Price (C.P.) is the price we bought the Share at. & Selling Price (S.P.) is the price we sold the Share at. After subtracting it; if the number you'll get is positive '+' then you can be sure of you earning a profit on this Investment. But in case it's negative that is in 'minus -' then it is a loss. This is a very basic & easy step