HSAs AND SS ACCOUNTS WILL MAKE OWNBERSHIP 100%:

Among the middle 20% of families, which earn an average of $49,600, almost half own some stocks, according to the Federal Reserve's Survey of Consumer Finances, one of the best available sources of wealth data. Among those earning in the 60th-80th percentile, or an average of about $80,000, almost 70% own stocks.

One of the key reasons that investors favor stocks is that, over the long run, the asset has historically performed very well. Thus it's no surprise that stock wealth grows with age. Even middle-income families who sock away some savings into the market over the course of their careers can have a substantial amount of stock wealth by the time they're near retirement.

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