Below 59+20 comes 59+15, then +10, +5, then a plain 59 and down through 58, 57. Stepping the S digit and leaving the suffix where it was turned 59+20 into 58+20, which nobody has ever said on the air. Five decibels at a time above S9 — the same increment sMeterRST rounds an S-meter reading to — and one S-unit below it.