I'm a little surprised that farmer/rancher isn't in the top 10. They have invested they're whole livelihood on the success of a crop or herd, hours are dawn to dusk, and that the market for their grain or cattle can sink like a rock in less than a week. Not to mention it's a thankless job when they help feed a world population of 7 billion. And their practices for producing safe, healthy food are under constant attack by social media. It's a tough job.