The format (and some of the numbers) depend strongly on the disk you use. Here's what mine displays (with lots of edits):
Code:
Device: SEAGATE ST336753LW
...
Error counter log:
Errors Corrected by Total Correction Gigabytes Total
ECC rereads/ errors algorithm processed uncorrected
fast | delayed rewrites corrected invocations [10^9 bytes] errors
read: 25504257 0 0 25504257 28315309 9329.822 20979
write: 0 0 0 0 0 3033.998 0
Non-medium error count: 15235
The error rate seems high, but it has not changed much since I forced the bad-sector relocation (which differs from a low-level format). That is what you keep your eye on.