Speaking as someone who has dealt with investors...
You damn well be able to put some hard numbers on that term if you're going to impress anyone.
The term "decent living wage" is not a meaningless one if you actually quantify it. This would actually be possible if you were dealing with a certain location and economic situation.
As with a lot of other terms used in politics, few politicians want to nail themselves down that tightly.
For a good time, ask a politician how much money one has to make to be "middle class," or "rich." Those terms are only useful in rhetoric if they float free, making emotional and not rational connections.