The percentage that a lawyer makes on a case may depend on a number of factors like his competence in the field and the amount of evidence given for the case. To analyze this, you may need to check previous records for a particular lawyer and check out how many cases he/she has been successful. Check also their educational background.
That's going to depend on the type of case. A defense attorney isn't going to make a percentage, but an amount agreed on by the attorney and client. An attorney who takes a case for, let's say, an injury/malpractice, usually gets 33% of the winnings.