Lunch topic : what percentage of people earned at least some income today?

[Mini 9]

A coworker is close to retirement and the topic of earning (and not earning) an income came up today.
It was hard to define at first, but we agreed that the above is a simple, fair (but odd) definition of earning and income. And then we wondered what percentage of the population earns anything on any given day.
Sorry, gossip is too easy.