Census estimates for North Dakota counties in 2018 were released last week.

Population estimates are produced by taking the population base from the last census (which was in 2010), adding births, subtracting deaths and adding international and domestic migrations (people moving out of an area). Estimates also reflect, according to U.S. Census Bureau notes, population changes due to “geographic program revisions” and the Count Question Resolution program-a program in which state, local and tribal officials could challenge a jurisdiction’s counts.

On April 1, 2010, Pierce County’s population was estimated to be between 4,357 and 4,359 residents. As of July 1, 2018, the estimate has dipped to 4,081 residents-a decrease of 278.

Cumulative estimates for Pierce County from April 1, 2010 to July 1, 2018 saw more births than deaths (374 births and 493 deaths) and 160 domestic migrations. From July 1, 2017 to July 1, 2018 Pierce County saw a decrease of 32 residents, which breaks down to 22 domestic migrations and nine more deaths than births (39 births, 48 deaths). Total population changes also include, according to U.S. Census Bureau notes, a “residual”, which is a change that isn’t able to be “attributed to any specific demographic component.”

Some nearby counties’ estimates also showed declines.

From April 1, 2010 to July 1, 2018, cumulative estimates showed a decrease of 250 residents in Wells County and 54 residents in Towner County.

However some nearby counties’ estimates showed growth.

Between April 1, 2018 and July 1, 2018, Benson County showed a positive population change of 302 residents; McHenry County showed a positive change of 424 residents; Rolette County a positive change of 362 residents; and Sheridan County a positive change of 28 residents.

Pierce County’s estimates were 4,366 residents in 2011; 4,447 in 2012; 4,4420 in 2013; 4,365 in 2014; 4,274 in 2015; 4,217 in 2016; and 4,113 in 2017. Estimates are used for multiple purposes, including federal fund allocations, community development and aiding business planning.

Official population figures will come from the next decennial census.