Last week, the Detroit News caught a small change in the city's population in new Census Bureau data: In 2014, the city's white population rose by nearly 8,000 people.

That's a relatively small number in a city of 680,000, but it's a significant change from the long-term trend over the lifetime of a majority of residents living in Detroit today. It means that the city's white population, which has dwindled through decades of suburban flight, is measurably growing for the first time since 1950.

"I was skeptical," says William Frey, a demographer at the Brookings Institution, when the Detroit media brought the news to his attention. "We have this long history of white declines in cities. It’s not just the last five years, 10 years, 15 years, it’s been going on in some places for even longer than that, and Detroit is one of them, clearly."

This modest new pattern is accurate, though: Go back to the 2010 census, and Detroit's white population has grown by a little more than 14,000 people. In just four years, the white share of the city's population is up 2.5 percentage points (to, well, 10.2 percent, still the smallest share of any major American city). Then Frey started to look beyond Detroit.

"And I became even more convinced when I looked at some of these other cities," he says, "that there was something going on."

Among the 50 largest cities in the U.S., nearly half gained a statistically significant number of whites from 2010-2014 (the change isn't significant in 21 of these 50 cities). Just 5 lost whites. That's compared to 35 cities where the white population shrank in the 2000s, and 31 in the 1990s. In Detroit, New Orleans, Washington and Denver, the white share of the population also rose over this same time.

Many a trend story has already looked at white millennials moving into changing neighborhoods in Detroit and New Orleans. And white population shifts have been clearer in cities that were seemingly national outliers, like New York and Washington. But this latest picture, from authoritative census data, means that their presence is starting to turn up at the city level in a broader way, and in some unexpected places. And the symbolism of that is particularly strong in Detroit, a city that has historically epitomized white flight. In 1950, Detroit was 84 percent white. By the 2010 census, it was 83 percent black.

None of this, though, necessarily means that we're at the start of the same kind of sweeping, long-term demographic re-ordering that began to escalate in U.S. cities in the 1950s (also missing from this current moment is the sheer scale of government intervention that enabled that earlier white flight).

"It’s not something to say we’re going to move 180 degrees in the other direction," Frey says of these new numbers. "And the white population isn’t growing as rapidly as it used to anyway. But it is an indicator that whatever kind of city revival — whether it's short-term or long-term that we’re seeing – is involving whites."

He still doesn't believe this will be a widespread pattern in the long term. But it's a surprise, he adds, to see it showing up in the first few years of this decade. What to make of the trend also depends on your point of view. While it may signal renewed faith in the city by a group that long ago abandoned it, demographic change also brings uneasy questions for the people who never left.