Foreign holdings of U.S. Treasury securities fell again in August as China, the biggest foreign owner of Treasury debt, trimmed its holdings for the third straight month.

The Treasury Department reported Tuesday that total foreign holdings dropped 0.8 percent to $6.20 trillion in August following a 0.5 percent decline in July.

China reduced its holdings 2.7 percent to $1.19 trillion after declines of 1.8 percent in July and 0.3 percent in June. Japan, the second largest foreign holder of Treasury debt, reduced its holdings by 0.9 percent to $1.14 trillion in August.

The Congressional Budget Office forecasts the national debt, now at $19.7 trillion, will increase by $8.6 trillion over the next decade, underscoring America's need to maintain high foreign demand for the rising levels of Treasury debt.

Last week, the government reported that the deficit for the 2016 budget year ended Sept. 30 totaled $587 billion, up 34 percent over the previous year. Under President Barack Obama, the government ran deficits topping $1 trillion annually for his first four years in office. But deficits had been declining since then.

China's holdings of Treasury debt have declined in nine of the past 12 months and now stand 6.7 percent below where they were in August 2015.

Total foreign holdings of Treasury securities are 1.5 percent higher than in August 2015.