This is based entirely on inference and testing with some mockups (basically a paper table saw and fence measurement I made). I am not a woodworker but I found this question interesting.
It's used to measure cuts for items wider than the table surface.
Your saw is 31 cm across, and you need to cut a sheet of plywood from 60 cm down to 55 cm.
Using your fence as currently marked you could....
1 - Lay your plywood on the table with the edge lined up on the left side of your picture (Where your measurements start, at the blade I'm guessing), to see you have overhang.
2 - Adjust the fence to 55 cm on the TOP row (6 cm on bottom)
3 - Line up the end to be cut with on the left side of the fence.
4 - CUT!
In our sample scenario this will cut off your excess 5 cm. I think the extra gap between 31-32 is for the width of your fence itself.
To phrase it another way, it looks like it's a way to cut the short end off of a very wide piece of material. The numbers increase to the left because the wider you want the sheet the less you will cut off.
You can't measure 55 cm cut off the 60 cm sheet, but you CAN measure the extra 5cm to cut off, and that's what those extra numbers are for.