What does 148 percentile on PSAT mean?

I got my PSAT scores a while back and underneath the "Your Selection Index" heading, it says:

Sum of scores in reading, math and writing skills

148 percentile

Compares your performance with college-bound juniors.


What does the percentile mean and what is the highest and what does 58 mean?

Thank you!


Your score is 148 and your percentile is 58.

Percentile is the percent of people you outscored on the test. Since you are in the 58th percentile, you did better than 58% of the college-bound juniors who took the test at the same time you did. This means you did slightly better than average.


I think that's a typo or an error, and you're in the 48th percentile.

You did better than 48% of college bound juniors, who got an average of 58.