The two digit score is NOT a percentile. It's meant for state licensing boards who want to look at scores similar to those that you might get in grade school, where 70 is passing. The score is also designed so that you can compare scores from year to year, which you can't do with a percentile (e.g. if someone gets 80th percentile in a year where everyone did remarkably well, it might look like they did worse than someone who scored 85th percentile in a year when people did worse).
Some faculty think of the two-digit score as a percentile, but this is an error. The USMLE website talks about the problems with percentiles and why they don't use them anymore.
Good luck!
