What would be the average ROI if I practice full-time Forex trading?

It depends on your account size.
If you are below 10,000$, most probably you can make it more than 10% a month.
If your account is large enough, you are good with like 30% a year.
Here is an example of gaining 40% in 6 months.

Regards,
Will Vu - Forex Investors since 2006

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