Measuring yard stick for violin sizing

Hi everyone! In the office hour on Monday, someone asked about sizing and I showed them a yard stick that I made one year at a PRSPW workshop. Here are the pictures of it and a close-up of the measurements. I believe that the stick is put at the neck on the collarbone and the marking should be at the crease of the wrist when the arm is straight out. Does anyone else have a stick like this who can confirm that? Thanks!