The rules permit a pattern day trader to trade up to four times the maintenance margin excess in the account as of the close of business of the previous day. If a pattern day trader exceeds the day-trading buying power limitation, the firm will issue a day-trading margin call to the pattern day trader. Margin can also be used for investing purposes to magnify your profits as well as your losses. Here’s a hypothetical example that demonstrates the upside; for simplicity, we’ll ignore trading fees and taxes. Assume you spend $5,000 cash to buy 100 shares of a $50 stock. A year passes, and that stock rises to $70. What if you worked on building up the cash to qualify as a day trading account per the SEC’s standards; however, you only use the cash on hand in your account. For example, let us say you have a $100,000 dollar account and instead of going for the full advantage of $400,000, you just trade the $100,000.