Once a role is at the interview stage you'll notice that these interview columns will update with scores that have the following structure (if you see 'n/a' in these columns, it means that interviewers haven't given their scores yet):
These are the main elements of an overall interview score given to each candidate:
a. Overall average. This is the average of all the scores that you see in the coloured grid.
b. Number of Questions/Sections included for the specific interview round. Each column represents one question / answer given by a candidate. In the case of the image above, the interview round had 3 questions.
c. Number of interviewers who scored each answer. Each cell within a same column represents the score given by a different interviewer to a same answer. In the case of the image above, the interview panel had 3 members.
d. Score given by an interviewer to a specific answer. Scores can range from 1 to 5. For your visual ease, the greener the cell, the higher is the score; the redder the cell, the lower is the score (a grey cell means that the score is pending).
This colour coding will make it easy to skim both the general and relative performance of a single answer and the level of disagreement between interviewers with regards to the quality of the same answer.