Alaska's Department of Labor and Workforce Development published the statistics in the March edition of Alaska Economic Trends.
The FNSB had a natural increase (birth rate) of 1,118 last year. But a decrease of 2,334 in net migration (in-migration minus out-migration) means the borough's population decreased by 1,216.
The number of borough residents in 2017 — 97,738 — is about 200 more than the 2010 census recorded.
Demographers do expect FNSB's population to grow, thanks to the arrival of F-35s at Eielson Air Force Base, according to the report.
Within the state, 699 people left Fairbanks for Anchorage, while 475 moved the opposite direction. Alaska's population decreased by 8,900 last year, the fifth year in a row of net migration losses.