How to display ‘Mistake Contribution %’ in a column out of total mistakes?

There are a total number of mistakes X, now I want to create a column for showing distribution for the total mistakes X, what will be the shorter name or better way to represent this?

Note: Total mistake will not be 100%, it can be 'x%',e.g. if a user has done 94% things right, I want to explain the distribution for his 6%