Hi @ConnorMcM,
Just to confirm, you want to be able to see how many company records have a phone number and how many don’t? What kind of visualization are you considering here?
As far as I know, this can only be achieved with a custom binary property (single checkbox), e.g. Company phone number known, that is populated by a workflow. You could then create a report based on this new binary property.
Alternatively, you would have to accept a visualization like the one below, where the big green chunk shows the number of records without a value for certain object:
Once you share more details, I’ll happily provide more help.