There are many guesses to what the actual piracy rate is. One thing is sure - it is high. The concept of morals was invented to help out when things simply couldn't be controlled.
Even if a product is heavily pirated, it is not certain that pirate users would pay the full price - even if pirate copies were eliminated. On the other hand, protection often allows the price to be reduced, thus giving the product a wider market and allowing it to out-compete unprotected products. In general, unprotected software is too expensive for legal users, since they are the ones actually paying for the piracy.
Our customers tell us that they often experience a considerable increase in sales as the result of applying good, safe protection: from 20 - 80 % compared to an unprotected product depending on the type of product. This figure is not necessarily worse in known "pirate" countries than in more "civilized" parts of the world.
Some like to release their first new launch for a region or for a product category unprotected - in order to get it spread around. When the market then wants the next version it pays to start using protection.
What you protect and how you do it, what drawbacks you will encounter and how this will affect your profit is a complicated matter. We are willing to share whatever we have learned from our customers. To tell the truth we have over the years had our own problems making sure that we got a fair share of the income our products earned.
Once we had a very active distributor that spread thousands of demo-diskettes trying to create sales for us. The demo diskette could be used to produce 10 real protected key-diskettes with protected programs on them. Just an appetizer. We were thankful to this distributor until we learned that he sold them for $ 20 each.
So trust and belief in the human nature is good - control even better.
If you insist on figures then try some of the Links.