30%

This appears to be the dividing line between middle eastern (and other nations) who have or will revolt. If any nation's people pays more than 30% on average for food of their yearly income based upon average wages within that country and if over 50% of the people are under 30 then you have the recipe for revolt.

If you are young and educated or uneducated and there are no jobs, no hope for a good marriage because of no jobs in a country, the threat of force means relatively nothing to such a person because they are dead if they don't try something. They have no hope at all for any future at all without revolt. So, force will not stop young people under 30 under these circumstances. This is a given almost no matter where these statistics arise on earth no matter the nation.

Here in the U.S. we only pay about 7% average for food based upon the average income. We are not in this category but about half the nations on earth or more are. The world is changing and likely will continue to.