To determine how well you are performing as an investor, calculate the profit or loss you make on each of your trades. The larger the profit, the better the investment. However, when you buy or sell a stock, you usually have to pay a broker a commission for the transaction. You also might receive dividends from the company while you own the stock, which should be included in the profit or loss because if the company did not pay out the money, the stock would be worth more.
Add the price of the stock purchase to the commission paid on the purchase to find the total purchasing costs. For example, if you paid $300 to buy a stock and paid a $12 commission, the total cost equals $312.
Add the sales price of the stock to the dividends received while you owned the stock, and subtract the commission paid to calculate your total receipts. For example, if you sold the stock for $350, received $10 in dividends, and paid $12 in commissions, add $350 to $10 to get $360 then subtract $12 to find your total receipts equal $348.
Subtract the total purchasing costs from the total receipts to find the profit expressed as a dollar figure. In this example, subtract $312 from $348 to find your profit equals $36.
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