SIOUX FALLS, S.D. (KELO) — Despite the delayed release of the 2020 U.S. Census redistricting data, many predicted trends remained the same. 

State Demographer and South Dakota State University professor Weiwei Zhang worked with the South Dakota Legislative Research Council to help organize some of the redistricting data into more user-friendly data. 

In April, the statewide data from the U.S. Census Bureau data showed South Dakota had an 8.9% growth rate from 2010 to 2020. And as predicted, the population growth came from cities like Sioux Falls and Rapid City. 

“The population growth is not geographically even and it follows the national pattern,” Zhang said. “The counties that are more metro or urban are seeing the majority of the growth.” 

The 2020 Census showed the population of U.S. metro areas grew by 9% from 2010 to 2020, resulting in 86% of the population living in U.S. metro areas in 2020, compared to 85% in 2010. In South Dakota, 64% (571,484) of the population lives in the 10 biggest counties, while 36% (315,183) lives in the other 56 counties.

“Smaller counties are becoming smaller,” Zhang said. “This is a trend in South Dakota and the nation as well.” 

The 2020 Census found nationally the “White alone non-Hispanic” population was at 57.8%, down from 63.7% in 2010. 

“That’s also happening in South Dakota even though at a slower pace,” Zhang said. 

In South Dakota, there was a “White alone non-Hispanic” population of nearly 80% in 2020, down from nearly 85% in 2010. Thirty-two of South Dakota’s 66 counties are more than 90% White alone. 

The American Indian and Alaska Native Alone population in South Dakota is at 8.8%, which is similar to the 2010 number of 8.5%. Nine counties are more than 50% American Indian and Alaska Native Alone with Buffalo County, Todd County and Oglala Lakota County all above 80%. 

“It’s stayed pretty steady,” Zhang said about South Dakota’s Native American population. “It doesn’t have a significant change.” 

Nationally, the Hispanic or Latino population was the second-largest racial or ethnic group, comprising 18.7% of the total population. In South Dakota, the Hispanic or Latino population rose from 2.7% in 2010 to 4.4% in 2020. 

“It’s a substantial change in the racial compensation of the state population,” Zhang said. 

Zhang noted growth in the people of color or non-white is both from migration and fertility levels. 

“The births,” Zhang said. “The fertility levels in the non-white population are consistently higher than the fertility among the white alone population.”    

With the 2020 Census wrapped up, Zhang said she expects to see many of the same trends continue once the 2030 Census is conducted. 

“The multi-racial and multi-ethic trend will continue,” Zhang said.  

Differential privacy creating data noise 

Another topic Zhang highlighted from the 2020 Census is the use of differential privacy, an algorithm that adds more “noise” for stronger privacy protections. 

Zhang said the Census Bureau’s technical team could find more than 50% of the individuals released in public 2010 Census data combined with some commercial data. 

“That basically raised the alarm of the data confidentiality,” Zhang said. “They are injecting noises to a great amount of Census data products.”  

State totals are not affected but all data underneath the state level have some type of data noises, Zhang said. 

“Rural counties will be affected more by this differential privacy,” Zhang said. “The Census had more focus on the block level.” 

She said the U.S. Census Bureau is strongly encouraging data users to combine groups of blocks together to “remove the fuzziness in the data.”