5% per month is actually nothing too hard to come by, as long as you know what you are doing as a trader, and you are not approaching the market without a strategy at all. What is important is to know the pairs you are trading, stick with a strategy and execute them pretty well without any emotion, look for a market that can easily go well with you plans and then you will see yourself doing pretty good over time.

However, this is not something that is impossible, considering the fact that in some cases, you can even make more than that, but when you are realistic with your potential earning, it is always a better thing than being too off the board.