*Consistency Explanation*
I don’t like using number like 6.5 or 6.25 frames because that kind of misrepresents how input lag works. A game cannot perform an action between frames, the action either occurs on frame 6 or frame 7. Using figures 6.5 represents that half the time the action occurs on frame 6 and the other half on frame 7, but this is kind of vague which is why I added the consistency rating. It clarifies how often a game is hitting the input with the lowest amount of input lag. Most games are actually consistent about what frames they respond on (hence 100%), but some games do alternate in responsiveness for whatever reason.
How I test for lag/my equipment setup: 
(link)