The percentage bars seem to be totally off.

• The ratio red/green doesn't match with the percentage
• Alignment is broken
• The length of the bars seem random to me

Suggestion. Move the percentage text up to the M: C: lines. This might fix the alignment issue.

The length (length red + length green) of the Red/green bar should be equal in length for all bars. The red/green ratio should reflect the percentage of the coverage.

Have a look at the attached screenshot (taken from Firefox 19 , Chrome shows very similar results)

Picture 2 42KB shows the issue.

Picture 1 (94KB) shows a possible solution for it.