Saving for retirement? Avoid stocks. Big-league.

That's according to you-know-who.

Donald Trump told Fox Business on Tuesday that the Fed's “artificially low” interest rates have pumped up stock market valuations.

“I did invest, and I got out, and it was actually very good timing,” the Republican presidential nominee said.

Sounds a bit like market timing, actually—jumping in and out of investments based on the news and on short-term performance. That's a strategy with a pretty bad long-term record.

Fidelity Investments looked at the returns for 401(k) savers who moved out of equities at or near the market bottom in late 2008 or early 2009 and stayed out as of the end of 2015, comparing them with returns for investors who kept a stake in stocks. The resilient investors were about $82,000 better off.

During the stock selloff last August, Trump told the New York Times that he'd gotten out of stocks three or four weeks before the Aug. 24 dive in the markets, but he advised investors to hold on to their stocks in the wake of the turmoil, saying, “I'd hate to see [the stock market] rebound and [investors] end up with the short end of both deals”—both selling at a low and missing any rebound.

It was good advice. From Aug. 25, 2015, to Aug. 1 of this year, the S&P 500 has risen 16.2 percent, and the Dow is up 17.5 percent.

Then, on Jan. 7, at a campaign rally in Burlington, Vt., Trump said: “By the way, speaking of stock. You see the bubble, a little bubble. It’s starting to go a little bad.” He went on, darkly: “Some bad numbers are coming out. Some really bad things. And you better be careful. Be careful.”

The market did take a painful fall in January. The S&P 500 was down 2.6 percent as of Jan. 6 and ended the month down more than 5 percent.

Still, a retirement portfolio should be structured so investors can live with market volatility. If a portfolio's equity stake has gotten out of whack due to appreciation in the stock market, sure, trim it back. But as Trump critic Warren Buffett has said, "You shouldn't own common stocks if a 50 percent decrease in their value in a short period of time would cause you acute distress."

Buffett has also said: "A prediction about the direction of the stock market tells you nothing about where stocks are headed, but a whole lot about the person doing the predicting."

How good a stock market investor is Trump? It's hard to say. In his book Crippled America, he wrote that 40 of 45 of his stock purchases “rose substantially in a short period of time.”

A Bloomberg story about that claim cited an analysis by Evercore ISI of 670 institutions that had held 20 to 50 stock positions as far back as 2011. “The New York-based research and investment firm measured both the positive strike rate, or the percentage of stocks that are positive each quarter, and the outperform strike rate, the ones that beat the S&P 500,” the story said.

It continued: “The record Trump claims, 40 positive out of 45 stocks, would put him in the 97th percentile among comparable institutions in the first quarter of 2015 and better than all of them in the second and third, according to ISI. Among hedge funds, he’d be in the 94th percentile in the first quarter and beat them all in the second and third.”

And that would be yuge.