The Vertex HV6 used to be supplied under a number of different marques. The one supplied by Myford looked just like mine, with a Myford badge instead of Vertex.
The spreadsheet was made up to cover the errors and omissions in the Vertex HV6, with a 90:1 ratio.
The HV 6 chart could be used to check that supplied with any other 90:1 ratio table, as long as the Division Plates are the same, in terms of numbers of holes.
If your table has a ratio other than 90:1, amending one of the formulae from 90 to the ratio of your table should result in a set of readings for yours.
I am not a mathematical genius, far from it, so it should be easy for anyone else, as long as you can use EXCEL.
Howard