2002 Chevy S-10 Blazer

2002 Chevy S-10 Blazer mileage: 120,000. I took a set of compression readings the other day, and need some help analyzing them. According to what I've read, these compression readings look good, but I've yet to see an actual number that would be acceptable. I just see "lowest cylinder must be 70% of highest, 100 psi min" does that mean Anything that falls into that range is fine. Anyway, here's the readings (took 3 readings each cylinder, averaged them. All 3 readings were within +/- 5 psi): Left bank Cyl 1: 163psi, Left bank Cyl 2: 144psi, Left bank Cyl 3: 146psi, Right bank Cyl 1: 160psi, Right bank Cyl 2: 130psi, Right bank Cyl 3: 146psi. I then added 3 squirts of engine oil to Rt bank Cyl's 2 and 3: Rt. Bank Cyl 2 w/oil: 135psi, Rt. Bank Cyl 3 w/oil: 140psi. Other helpful info may be that when I pulled spark plugs, Cyl 2 on both sides were coated with heavy black dry (carbon?) Deposits, and Cyls 3 on both sides were coated with a good amount of oil. Cyls 1 on both sides looked to be ok. Any help on what all this means would be greatly appreciated!