I don't play it, but I noticed that some putters' scales are not full fractions of the whole scale.
My Rossa has an odd division in the 90 ft scale, movements at 13(,33) %, 27, 40, 53, 67, 80, 93 %, leaving a short 7% for the last area.
Perhaps your putter's movements are a fraction of the 25 or even 50 ft scale? A wild guess: 10 ft?
Perhaps you have a putter pal available to check it, or fix a ruler at the screen?
Or try my paper pal: