I don't know the current percentage, but it used to be that 70% of the biopsies were negative, so here's hoping yours is, too. My psa was always +/- 2.8, then in one year it went to 4.85, so the uro said a biopsy was in order. With no history of PCa, I instead chose a course of Levaquin to see if it might infection. Since my psa was then still 4.8, I did a biopsy, which found 7 out of 12 core samples positive! 4 were Gleason
2+3, and 3 were 3+4, which means I was a Gleason 7. I chose to do proton therapy last summer, and it was an incredibly positive thing. With this kind of therapy, your psa comes down slowly over 2 years. At 9 months, mine is now 1.05 and falling steadily, so I couldn't be happier! I know lots and lots of guys with relatively high psa's (some over 20) who have had several negative biopsies. In most cases, their higher psa was related to an enlarged prostate, which is not uncommon as guys age. I am pushing 65 and have never had the enlarged problem fortunately.
As to free psa, I think the range is between 10-20% for a potential PCa. Anything lower than 10% they assume it is a given, over 20% assume it does not exist. After treatment, I'm not sure what the point of even looking at it is, although they do it regularly.