This is the original list.
This is my new List.
I don't see any structural problems with the formula but I have a few suggestions.
1. Break up your formula into the component parts (this is suggested in the PLANS methodology). This will help you determine where the error is.
2. Don't use list properties. Create a system module. This is a much better way to work with the properties of the list. More efficient, and easier to work with formulas. DISCO!
You are missing single quote signs ' in your formula, it should be VALUE(NAME(ITEM('02Hours'))) - 1
However, as @JaredDolich already indicated, try to follow best practice and create System Module to perform any calculations and store attributes instead of creating properties. As one of the reasons, it would be also easier for you to write the formula after typing VALUE(NAME(ITEM( you can then just click on the list name. This way, you will always get proper list name and add single quote signs automatically. It will make things easier for you!
As always you are the Messiah.
It was my mistake.
Thanks for explaining.