According to the 1995 Annual Report of the Federal Reserve Bank of Dallas, only 5 percent of those in the bottom 20 percent category of income earners in 1975 were still there in 1991. What happened to them? A majority made it to the top 60 percent of the income distribution -- middle class or better -- over that 16-year span. Almost 29 percent of them rose to the top 20 percent.
The evidence suggests that low income is largely a transitory experience for those willing to work. There's no mystery to it: As a function of age, people get wiser and gain more experience. That means it's not very intelligent to think one can make meaningful statements about poverty simply by measuring income at a particular point in time. By the way, people are also mobile downward, as suggested by the joke that the easiest way to become a Texas millionaire is to start out as a Texas billionaire.
Here's Williams' roadmap out of poverty: Complete high school; get a job, any kind of a job; get married before having children; and be a law-abiding citizen. Among both black and white Americans so described, the poverty rate is in the single digits.