KABUL, Afghanistan — The Afghan government’s control of its country declined late last year, in terms of both territory and population, according to a United States government report released Thursday.

The report, by the agency of the Special Inspector General for Afghan Reconstruction, or Sigar, said that as of Oct. 31, the Afghan government controlled territory on which 63.5 percent of its population lived, a decrease of 1.7 percent from the previous quarter, while gains by the Taliban insurgency gave it control over territory that is home to 10.8 percent of the population.

The agency’s statistics are based on data provided by the American military under a mandate to report to Congress quarterly.

In addition, the Afghan government lost control of seven more districts during the last quarter, meaning that only 53.8 percent of districts were “controlled or influenced” by the government, while 12.3 percent of the districts were under insurgent control or influence and 33.9 percent of districts were contested. Afghanistan’s 407 districts are the basic unit of local governance.