Between 2003 and the end of 2004, the AUD/USD currency pair offered a positive yield spread of 2.5%. Although this may seem very small, the return would become 25% with the use of 10:1 leverage. During that same time, the Australian dollar also rallied from 56 cents to close at 80 cents against the U.S. dollar, which represented a 42% appreciation in the currency pair. This means that if you were in this trade – and many hedge funds at the time were – you would have not only earned the positive yield, but you would have also seen tremendous capital gains in your underlying investment. 
When scalping, traders tend to employ a leverage that starts at 50:1 and may go as high as 500:1. Knowing the effect of leveraging and the optimal leverage Forex trading ratio is vital for a successful trading strategy, as you never want to overtrade, but you always want to be able to squeeze the maximum out of potentially profitable trades. Usually a trader is advised to experiment with leverage within their strategy for a while, in order to find the most suitable one.
Trading leverage or leveraged trading allows you to control much larger amounts in a trade, with a minimal deposit in your account. Leveraged trading is also known as margin trading. You can open up a small account with a brokerage, and then essentially borrow money from the broker to open a large position. This allows traders to magnify the amount of profits earned. 

When a trader decides to trade in the forex market, he or she must first open a margin account with a forex broker. Usually, the amount of leverage provided is either 50:1, 100:1 or 200:1, depending on the broker and the size of the position that the investor is trading. What does this mean? A 50:1 leverage ratio means that the minimum margin requirement for the trader is 1/50 = 2%. A 100:1 ratio means that the trader is required to have at least 1/100 = 1% of the total value of trade available as cash in the trading account, and so on. Standard trading is done on 100,000 units of currency, so for a trade of this size, the leverage provided is usually 50:1 or 100:1. Leverage of 200:1 is usually used for positions of $50,000 or less.

It should be remembered that leverage does not alter the profit potential of a trade; but instead, reduces the amount of equity that you use. Leveraged trading is also considered a double-edged sword, since accounts with higher leverage get affected by large price swings, increasing the chances of triggering a stop-loss. Therefore, it is essential to exercise risk management when it comes to leveraged instruments.

In forex, investors use leverage to profit from the fluctuations in exchange rates between two different countries. The leverage that is achievable in the forex market is one of the highest that investors can obtain. Leverage is activated through a loan that is provided to an investor by the broker that is handling the investor’s or trader’s forex account.