Minnesota’s most diverse places are becoming more and more diverse, really quickly.

That’s the lesson from the latest round of county race and ethnicity estimates from the U.S. Census Bureau, which bring us up to 2015 and so amount to a mid-decade update.

The biggest jumps in minorities as a share of population happened in the two counties — one rural (Nobles), the other urban (Ramsey) — that started the decade as the state’s most diverse, at least outside of Indian Country.

But this decade also has seen a pair of symbolic moments of interest in the suburbs as well:

• No longer is any Twin Cities suburban county at least 90 percent non-Hispanic white, long held as a sure sign of homogeneity;

• A suburban county — Dakota — has reached a milestone in becoming “truly diverse,” with others sure to follow.

The biggest shift from 2010 to 2015 took place in Nobles County, in the state’s southwest corner, where Worthington is the county seat. Minorities in Nobles rose by a whopping 6 percentage points, far higher than in any other county. Strong in Latinos, Nobles dropped from 67 to 61 percent white.

In the metro area, Ramsey County saw a 4-percentage point drop in its white population, from 67 to 63 percent. Census analysts reckon that more than any other metro county, Ramsey owes its population growth almost entirely to people of color.

The biggest jump in minority numbers came in Hennepin County, which added nearly 45,000 to slide just slightly from 72 to 70 percent white. At a strapping 1.2 million, Hennepin is more than twice Ramsey’s size and, unlike its sibling, added lots of whites as well — roughly 26,000 in five years. All metro counties did see a jump in whites.

Four of the five purely suburban counties in the metro area saw similar percentage point drops in the non-Hispanic white share of their populations. Dakota County went from 82 to 80 percent white, while Scott, Anoka and Washington counties all dropped from roughly 85 to 83 percent white.

Carver County, the least diverse in the metro group, also saw the least change by this measure, dipping from 91 to 89.5 percent white. Carver was the site of a notably ferocious battle over racial change, as citizens in the city of Carver tried to fight off the arrival of a Metropolitan Council-supported affordable housing project in the face of City Council warnings that businesses were seeing staff shortfalls in certain types of jobs.

Carver and Scott were the only metro counties that saw more growth among whites than minorities, due in part to birthrates from young families who moved in during fast-growth periods.

The latest estimates mark a symbolic turning point of sorts: No longer is any one of the seven metro counties officially 90 percent white, the hallmark of traditionally ultra-white Midwestern suburbia.

In fact there’s double symbolism at mid-decade: Some analysts consider a city or council officially “diverse” once its minority share has reached 20 percent, and that has now happened in purely suburban Dakota County.

The most diverse county in the state, indeed the only county with a majority of minority group residents — 53 percent people of color — is lightly populated Mahnomen, in the northwest, which includes part of the White Earth reservation.

The least diverse is farm-dominated Fillmore County, in the southeast; only 2.9 percent of its residents, in the county that includes tourism draw Lanesboro, are people of color.

To see where Minnesota counties stand, go to tinyurl.com/zajcjbq/.