that people from the lower class have not come in the middle class as much as they had earlier
When famous economist Chetty et. al. [1] at the Harvard Equal Opportunity project went to prove this, they were surprised to find it's not true. They obtained never before access to lifetime IRS income statements to see how people moved over time, and they found that social mobility has not changed from around 1960 on. (Other studies had already shown this to be true for the first half of the 20th century). Other studies since theirs have obtain similar results. Here's a summary article about their results [2].
Comments
When famous economist Chetty et. al. [1] at the Harvard Equal Opportunity project went to prove this, they were surprised to find it's not true. They obtained never before access to lifetime IRS income statements to see how people moved over time, and they found that social mobility has not changed from around 1960 on. (Other studies had already shown this to be true for the first half of the 20th century). Other studies since theirs have obtain similar results. Here's a summary article about their results [2].
[1] https://scholar.google.com/scholar?hl=en&as_sdt=0%2C15&q=che...
[2] https://www.cfr.org/blog/new-harvard-study-us-social-mobilit...