Hi @d.norkus
There is no document on the server. To return the value, make sure the last line evaluates to the value.
For example:
var x = 100 - Math.abs(100-(100*a/b));
x;
You could leave the last line out, as the variable assignment in this case evaluates to the same thing, but there are cases where that isn’t true, and I prefer to be explicit about what is being returned.