On Nov. 27, 2013, a Madison-based liberal advocacy group used a mass email to promote protests that were planned against Walmart stores for two days later -- Black Friday.

The demonstrations aimed to "expose Wal-Mart’s shameful labor practices and support workers," according to One Wisconsin Now, which then made this claim:

"The Walton family , which owns Wal-Mart, controls a fortune equal to the wealth of the bottom 42 percent of Americans combined."

That reminded us of a March 2011 claim by filmmaker and liberal activist Michael Moore.

He said in a Madison speech that 400 Americans have more wealth than half of all Americans combined, a statement we rated True . Based on online hits, it became one of our most popular fact-checks ever.

So we wondered about the Walmart claim.

Wealth, not income

In the days before and after Black Friday, leaders no less prominent than President Barack Obama and Pope Francis decried the extent of income disparity in the United States and around the world. Obama called the growing income gap a "defining challenge of our time." The pope said that while the earnings of a minority "are growing exponentially, so, too, is the gap separating the majority from the prosperity enjoyed by those happy few."

Walmart, of course, is a big target.

According to Forbes , as of May 2013 the international retailer had $469 billion in sales and 2.2 million employees, including 1.3 million in the United States. The corporation has been criticized for low wages; and in December 2012, PolitiFact National rated as Mostly True a claim that more Walmart employees are on Medicaid and food stamps than other companies.

But let’s be clear up front: Although income and wealth are related, they’re not the same.

Wealth is commonly measured in terms of net worth -- the value of a person’s assets minus liabilities. So, things like savings and retirement accounts, minus what is owed on a home mortgage, credit cards, etc. That means a person with heavy debt can have little wealth, or negative wealth, even while earning a six-figure income.

One more point before we get to the wealth figures.

Walmart was founded by the late Sam Walton , who opened the first store in Arkansas in 1962. Walmart incorporated in 1969 and became a publicly traded company a year later. So, Wal-Mart is not family owned, but rather owned by its stockholders; on the other hand, according to Bloomberg and other news reports , the Walton family members still have control of the company, owning about half of the shares.

Group's evidence

Scot Ross, One Wisconsin Now's executive director, told us his evidence to back his group’s claim is a July 2012 article by economist Josh Bivens , research and policy director of the liberal Economics Policy Institute in Washington, D.C.

Bivens wrote that in 2010, the wealth of six Walton family heirs was $89.5 billion, 22 percent higher than in 2007.

Meanwhile, the median wealth of American families in 2010 was $77,300, nearly 39 percent lower than three years earlier.

(Median wealth refers to the American family that is exactly wealthier than half of all families and less wealthy than half.)

As for measuring one against the other, Bivens said the Walton family wealth in 2010 was as large as the wealth of the bottom 48.8 million families in the United States, or 41.5 percent of all American families.

Rounded up, 41.5 percent would be 42 percent, the figure One Wisconsin Now claims.

But let's keep shopping around a little.

Similar claim

It turns out that a statement nearly identical to the one made by One Wisconsin Now was uttered in July 2012 by U.S. Sen. Bernie Sanders, a Vermont independent who caucuses with Democrats.

Sanders said the Walton family owns "more wealth than the bottom 40 percent of America," a claim PolitiFact National rated True .

Our colleagues found that Sylvia Allegretto , a labor economist at the University of California, Berkeley, compared the Waltons’ cumulative net worth with that of the overall population, as cited in the Federal Reserve’s Survey of Consumer Finances. That survey was published in August 2012.

Allegretto found that the Waltons’ wealth in 2010 was valued at $89.5 billion -- equal to the entire bottom 41.5 percent of American families.

The 2010 figures are the latest available for doing comparisons with the net worth of the overall population.

But we found, using the Forbes 400 list for 2013 , that the wealth of six of Sam Walton’s descendants has continued to grow. Here are their rankings and their wealth:

No. 6 Christy Walton (daughter-in-law), $35.4 billion

No. 7: Jim Walton (son), $33.8 billion

No. 8: Alice Walton (daughter), $33.5 billion

No. 9: S. Robson Walton (son), $33.3 billion

No. 95: Ann Walton Kroenke (niece), $4.7 billion

No. 110: Nancy Walton Laurie (niece), $4 billion

Total Walton family wealth: $144.7 billion.

A note before we close:

Allegretto told us the housing crisis is a key reason that the gap between the Walton family wealth and the wealth of other American families has grown. More Americans were left with "negative wealth" because they lost their biggest asset -- their home -- and often significant amounts of their savings, as well, she said.

Our rating

One Wisconsin Now wrote: "The Walton family, which owns Wal-Mart, controls a fortune equal to the wealth of the bottom 42 percent of Americans combined."

For comparison purposes, the latest data available, for 2010, the figure is 41.5 percent.

We rate the statement True.

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