Donald Trump is a billionaire and he plays it up big in his bid to be president. What he did in business, he argues, he can do for the country.

Republican and Democratic critics aim to shoot holes in that assumption. One tack is that Trump hasn’t been the super savvy investor he purports to be.

The liberal group Occupy Democrats posted an image on its Facebook page on Dec. 2, 2015, to bring Trump down a notch or 10. Under a smiling photo of Trump, the image has these words:

"Bloomberg puts Trump’s current net worth at $2.9 billion. ... If Trump had just put his father’s money in a mutual fund that tracked the S&P 500 and spent his career finger-painting, he’d have $8 billion."

The source, included in the post, is Deborah Friedell with the London Review of Books.

As it turns out, the graphic from Occupy Democrats did a fine job of quoting Friedell, but Friedell did a less than stellar job of quoting the source for her claim.

Friedell’s words come from her review of a new biography of Donald Trump, Never Enough: Donald Trump and the Pursuit of Success by Michael D’Antonio. Here’s the full text relevant to this fact-check:

"Bloomberg puts Trump’s current net worth at $2.9 billion, Forbes at $4.1 billion. The National Journal has worked out that if Trump had just put his father’s money in a mutual fund that tracked the S&P 500 and spent his career finger-painting, he’d have $8 billion."

But if you read the National Journal story, it doesn’t directly tie whatever money Trump got from his father to an eventual $8 billion today. Here’s the key paragraph from a Sept. 2, 2015, article headlined " The 1 Easy Way Donald Trump Could Have Been Even Richer: Doing Nothing ."

"Had the celebrity busi­ness­man and Re­pub­lic­an pres­id­en­tial can­did­ate in­ves­ted his even­tu­al share of his fath­er’s real-es­tate com­pany in­to a mu­tu­al fund of S&P 500 stocks in 1974, it would be worth nearly $3 bil­lion today, thanks to the mar­ket’s per­form­ance over the past four dec­ades. If he’d in­ves­ted the $200 mil­lion that For­bes magazine de­term­ined he was worth in 1982 in­to that in­dex fund, it would have grown to more than $8 bil­lion today."

There’s a bit of informed guesswork behind these numbers because outsiders can only know so much about Trump’s finances. The National Journal writer, S.V. Dáte, figured Trump started with $40 million in 1974. That’s the year he became president of his father’s real estate company. By one estimate, the firm was worth about $200 million and divided among Donald Trump and his four siblings, each would have received $40 million.

But it’s not as though the company was liquidated that year. Trump’s father lived until 1999, so whatever happened, it’s more complicated than Trump receiving a cash inheritance in 1974 and deciding what he would do with it.

We’re left with a question of how much money Trump got from his father and, most important, at what point those assets morphed from being his father’s to being his.

In 1982, after running his father’s firm for eight years, Forbes magazine estimated Trump’s worth at $200 million. Since he was in charge of the company, then those dollars are more his than his father’s. The Journal article tiptoed around this uncertainty with careful phrasing. The author talked about Trump investing "his eventual share of his father’s real estate company." An eventual share is not cash in hand.

Similarly, the article did not say that the estimated $200 million in 1982 was from Trump’s father. Dáte told us in his view, that truly was Trump's money because the real estate company was worth more than that. Dáte said he didn't really care what the status of the assets was.

"I just wanted to get to the point of saying that given the amount of money he started with, to be a billionaire — it's not too hard," Dáte said. "I worded it as carefully as I did because there are a lot of uncertainties."

Importantly, if the $200 million did not come from Trump's father, then you can't say that the father's money could have been worth $8 billion today.

But the Occupy Democrats’ Facebook post took a paraphrase of the National Journal piece and then edited the paraphrase down to the text on the image. Occupy Democrats editor Omar Rivero didn’t defend the graphic he shared. Rivero said his group occasionally shares graphics made by others.

"As you can see in the post description and in the watermark, this graphic was made by Santa Pegatina, a political graphics maker," Rivero said.

The best summary of the National Journal article is that it presents a hypothetical investment scenario using numbers that have some basis in the value of the Trump holdings, but aren’t necessarily what Trump got directly from his father.

Running the numbers

Even if the underlying assumptions are dodgy, the math at least is in the ballpark.

We used $40 million as the starting point for 1974. Honghui Chen, associate professor of finance at the University of Central Florida, told us the account would have grown to $3.94 billion by November 2015 if the money had followed the S&P 500 index and all dividends had been reinvested.

This is a rough calculation that ignores taxes owed on dividends, but it’s on the same scale as what the National Journal reported.

Chen said it’s trickier to calculate the value of $200 million invested in 1982.

"Because the stock market in 1982 was quite volatile, the current value of $200 million investment in 1982 would depend on the time at which it was initially invested," Chen said.

If it went in right at the end of 1981, it would be worth $6.7 billion. Invested in June 1982, the value today would be $8.3 billion. Invested at the end of 1982, it would be worth $9 billion. Again, in the neighborhood of what the Journal said.

There is a huge debate over Trump’s current net worth. Estimates from outsiders, such as Bloomberg and Forbes, range from about $3 billion to about $4 billion. Trump says he has closer to $9 billion.

Our ruling

Occupy Democrats shared an image that said if Trump had taken the money he got from his father and simply put it in a fund that tracked the S&P 500, he’d have $8 billion today. While it's true that Trump got a leg up from his father on the order of many tens of millions of dollars, this specific claim suffers from a key flaw.

The only way to hit the $8 billion mark is to start with $200 million in 1982, and it's wrong to say that was Trump's father's money. While the father's business put Trump on the path to have $200 million in 1982, Trump himself had been running the company for eight years.

We rate this claim False.