2017 saw a big jump in U.S. millionaires. It appears most of them greatly benefitted from surging stock markets.
Michael Smith at Houston's STA Wealth Management says they stayed the course.
"The key for these people is they've stayed invested in the stock market and kept to it over the last eight years, where we've seen a big run-up in the markets."
Smith says most of the new millionaires took advantage of the long-running bull market, but they need to be wary.
"This is a time to be conservative; this market has run here eight years going into nine and it would be time to make an adjustment and really make sure you understand the risk you have to the downside."
Smith says another key is frugality.
"The more success that I see every day when I sit down with somebody is their ability to be frugal and spend less than what they make and save."
Smith says if you get a few hundred grand and spend it on luxury cars, homes and vacations, you may not become a millionaire. Lots of millionaires work long hours, drive old cars and live in relatively modest homes.
The U.S. set a new record for the amount of millionaires -- over eleven million.