For the most part, yes. Most people do end up working jobs just to make ends meet. What percentage of income do most people probably get to save is going to fluctuate, a ton. You might have 10% of people who are between the ages of 16 and 21, who live at home, that might save 70% of their money VS. someone who is aged between 26 and 31, has their own apartment, pays rent, electric, water, car insurance, phone bill, etc. and lives paycheck to paycheck, who might only save 15% of their income.
There are so many factors to consider, that some overpaid person who does things like this for a living, would have to conduct a study to try and find that out.