A.T. McWilliams is a writer and poet based in Oakland, Calif.

The 400th anniversary of slavery in the United States coincides with a Democratic presidential primary in which reparations for slavery have played a surprisingly prominent role. Marianne Williamson proposed providing up to $500 billion in repayment to black Americans, while Sen. Cory Booker (D-N.J.) has reinterpreted reparations through “baby bonds” and a proposed measure to study the effects of slavery.

Though reparations may not be broadly popular, their economic value is undeniable. Closing the racial wealth gap stands to stimulate an entire nation, adding an estimated $1.5 trillion to the U.S. economy.

To do that, though, we need to reckon not just with the value of the unpaid labor performed by generations of slaves but also with the impact of land thefts that cost freed slaves the most important asset they acquired in the years following emancipation. It may be challenging to calculate what a cotton-picker’s wages might have been in the absence of a free labor economy and how those wages might have grown into wealth over generations. But we have always assessed the value of land in blunt terms. Reparations for land thefts wouldn’t just put a stark number on what was stolen from black Americans, it would force us to reckon with the idea that the Emancipation Proclamation does not represent a clear dividing line between one era of American history and the next.

The concrete case for reparations begins with individual stories — stories like that of my great-great-grandparents, Elias Charles and Luisa Wingate, and kept alive by people such as my 84-year-old grandmother, Wanda Crow.

Elias, whom Wanda joyfully describes as “a handsome and deeply dark-skinned man,” was born just three years before the Emancipation Proclamation was signed. In his twenties, Elias moved from Darlington, S.C., to Gurdon, Ark. Bent on reaping the benefits of their freedom, Elias and his wife, Luisa, arrived in Arkansas, founded a church and purchased more than 150 acres of land.

They weren’t alone in this specific pursuit of the American Dream. By 1910, the peak of black land ownership in U.S. history, black people owned 15 million acres of land . But their holdings fell nearly 85 percent, to 2.3 million acres, by the late 1990s. Much of this decline did not happen by accident.

In my grandmother’s telling, Elias’s untimely passing left Luisa to look after the land they’d purchased, now home to chickens, cows and other farm animals. To contain them, Luisa bought barbed wire from a local white family and agreed to pay off her purchase over time. But after missing one payment, which my grandmother recalls as “less than $50,” the white family swiftly seized her only asset: the land — roughly 150 acres, taken over a meager bushel of wire.

My family believes that Luisa, a black woman navigating the South mere decades after slavery’s end, was illiterate — as was the case for 80 percent of nonwhite people in the late 1800s. It is also unlikely that she had access to a lawyer, or that she could place her faith in the Jim Crow law enforcement. Luisa was, like many black families of her time, defenseless. And, as a result, she was left devoid of assets — and hope. Soon after, my great-great-grandmother Luisa moved to Detroit in search of work and a new life.

It’s impossible to go back now to verify this account with certainty. Many black people’s stories of coercively seized land resemble my family’s: They are preserved in oral tradition but not formally documented. Though these incidents were deplorable, says Mary Frances Berry, a professor at the University of Pennsylvania, they were common, as were tactics such as the ones that robbed my family of our land.

The consequences of such thefts ripple through generations. According to a 2015 report, land in Arkansas today is worth roughly $6,739 per acre, valuing the approximately 150 acres my family lost at more than $1 million. The loss of that land dramatically shifted our family’s financial trajectory across generations. Even if Luisa and her descendants had not been able to farm it successfully, if the family had been able to hold on to the land and sell it at a fair price, that asset could have laid the foundation for a very different future.

We are not alone. Though the issue of land loss has recently returned to public attention, this part of our history has been well reported and understood for years. In 2001, the Associated Press published a thorough investigation into the heinous loss of land experienced by black families like mine. Interviews with 406 victims whose families lost 24,000 acres of land worth tens of millions of dollars unearthed harrowing stories of pilfered properties. Some thefts were accomplished by legal subterfuge, others through lynching. Lost land continues to be the driving factor of America’s billion-dollar debt to black people. The result of that debt means that the average black family would need 228 years to amass the wealth of an average white family.

So to the presidential candidates who have expressed support for reparations but failed to share concrete proposals, what is your strategy to repay black slave descendants ? Your future constituents deserve to know. And when the complex but solvable question of “how” inevitably deters your action, think first of families such as mine — families whose ancestors lost millions a short century ago, and have been distanced from the American Dream as a result.

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