Notice that there may be some blanks for extreme low and high readings. If a 2mm spoke reads 16 or less from the tool, the tension is below 51 Kilograms. This spoke would be quite loose. However, a 3.2mm x 1mm bladed steel spoke is 89 kgf when the tool reads 14.
The table does not include separate columns for butted spokes. In testing spokes at the Park Tool Company, it was determined there was no significant difference between straight diameter spokes and butted spokes. A butted spoke is basically considered a shorter straight gauge spoke.
The pointer of the tool will point at a number on the scale. For more accurate tension results, the tool can be read to finer precision. If the point repeats just off a number, the reading can be quartered. For example, the image below shows an example of a 24, a 24.5, a 25 and a 25.25. The 25.25 show the pointer just off the 25 mark.