"For the top 1% of wealth holders from 1989 to 2013, inherited wealth accounted for only 17% of their assets. (The 1%, in this analysis, is an overwhelmingly self-made group.) By contrast, for those with assets of just $25,000-$50,000, inherited wealth accounted for 52% of their worth."
https://www.wsj.com/articles/review-how-the-richest-got-that-way-1513036026
https://www.wsj.com/articles/review-how-the-richest-got-that-way-1513036026