Hi, I'm going crazy with a 'simple' graph that I'm trying to make; better than million of words, a picture (attached).

Can someone tell me why the grey line (but not only it,also the other two have the same types of problems) is completely wrong? Notice that:
- left point value: 43 -> this one is the only one in the correct position
- middle point value: 8 -> wrong!between line 20 and 30
- right point value: 15 -> wrong!above line 50 and above the left point!

thank you!

mik

Attached Images

exc.png (60.7 KB, 20 views)