The death rate among Afghan security forces is surging far above last year's levels, a US government watchdog said Sunday, and slew of social gains in the war-torn nation is also eroding.

Afghan forces are nearing the end of their second year providing security across their war-torn country, after NATO moved into an advisory and training role -- and the toll on the local forces has been devastating.

2015 was a terrible year, with an estimated 5,000 killed and another 15,000 wounded, primarily by the Taliban.

But the death toll this year is already much worse: From January 1 through August 19, a total of 5,523 Afghan service members were killed, according to a quarterly report from the office of the Special Inspector General for Afghanistan Reconstruction (SIGAR).

An additional 9,665 members were wounded during the same period, the report found.

Violence from the Taliban and other insurgent groups typically spikes over the summer during the "fighting season."

But increasingly, militants continue launching attacks throughout the year, meaning the death rate will likely rise further still.

"The most immediate challenge to the US reconstruction effort, and to the viability of the Afghan nation state, remains the armed insurgency pursued by the Taliban and other factions," the inspector general, John Sopko, said in the report.

US Army General John Nicholson, the top US and NATO commander in Afghanistan, warned a week ago that basic leadership failures in many Afghan police and military units were helping drive casualty rates higher.

Still, SIGAR found, morale within the ranks appears good, with three-quarters of recruits saying they have received good care and 90 percent satisfied with their pay.

The report also found that gains in key social areas such as poverty, unemployment, women's rights and the education gender gap have all eroded this year.

"Deep-rooted cultural traditions and a persistent insurgency continue to threaten the physical safety and health of Afghan women and hold them back from entering public life," the report states.

The Afghan government still only has full control of two-thirds of the country's population of 30 million.

Ten percent is in Taliban hands, and the rest is still being fought over.

This summer's fighting saw the Taliban try at least seven times to seize a provincial capital, as they did in Kunduz last year.

The Afghans managed to repel these thanks to NATO support, easier rules for the United States to strike targets and the growing confidence of the Afghan air force.