I think we don't need such statistics. The number of scammers in all countries will be approximately the same, but not everyone has access to the necessary means of distributing such information. Very often, people become victims of scammers when they lose hope of earning money in a legal way and use such Ponzi schemes as the last opportunity to fix their financial situation.
It is completely false, people tend to find attractive returns and jump onto ponzi schemes, in real world you cannot expect multiple returns by investing your money in stock or bonds in a short period and all they know is that the cryptocurrency world will provide instant profit and that is how majority jump into these scams.