Worldwide human trafficking convictions rose in 2016 and the number of victims declined, the State Department announced Tuesday in a report that found China has done little to combat the problem.

In its newly released annual "Trafficking in Persons" report, the State Department found that global prosecutions for human-trafficking crimes fell about 22% to 14,897 prosecutions last year, from 19,127 in 2015, while the number of global victims identified fell about 15% to 66,520 in 2016 from 77,823 in 2015.

At the same time, worldwide convictions for human trafficking crimes rose about 37% to 9,071 in 2016 from 6,615 a year earlier.

Prosecutions had risen every year since 2012, while convictions had climbed every year since 2014. The number of victims identified, meanwhile, had increased each of the past two years, data in the report showed.

Those figures and patterns indicate progress but outline the monumental task still faced by both the State Department and the Trump administration in making good on the president's goal to fight the “epidemic” of human trafficking with the “full force and weight” of the U.S. government

“Human trafficking is as old as humankind,” Secretary of State Rex Tillerson said Tuesday at a press conference to announce the release of the 2017 report. “It is our hope that the 21st century will be the last century of human trafficking.

“Regrettably, our challenge is enormous,” he added. “We have a lot of work to do and governments around the world have a lot of work to do.”

This year's report included summaries of efforts to fight global trafficking in 187 countries and territories, including the U.S.

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In his remarks, Tillerson took aim at China, which his department’s latest report called out as one of the worst offenders, placing it the lowest possible category — Tier 3.

According to the State Department, nations in Tier 3, which also includes North Korea, Syria, Sudan, Iran and Haiti, are failing to meet minimal standards to prevent human trafficking or to take actions that would improve efforts to fight such trafficking.

“China was downgraded to Tier 3 status, in part, because it has not taken serious steps to address its own complicity in trafficking, including (on) forced laborers from North Korea that are located in China,” Tillerson said.

“The North Korean regime receives hundreds of millions of dollars a year from the fruits of forced labor. Responsible nations simply cannot allow this to go on," he added, in a nod to the fact that money from that forced labor in China is used to fund North Korea's nuclear program.

Tillerson made similar remarks last week, as part of a broader effort by the Trump administration to ramp up pressure on China to exert more economic influence on its rogue neighbor.

State Department spokeswoman Heather Nauert said “other forced-labor concerns” came into play for the downgrade, too, including NGO reports about the Chinese government’s “complicity” in situations where “individuals continue to be detained without judicial process.”

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News of China’s expected downgrade had emerged Monday evening, prompting the country to hit back by Tuesday morning, before the official release of the 2017 report. “As we have said repeatedly, no country has the right to speak irresponsibly on China’s domestic affairs,” China’s Foreign Ministry Spokesman Lu Kang told the Associated Press.

Countries in Tier 3 may be penalized with economic sanctions, although the President has the authority to wave those sanctions.

The State Department now has 90 days to decide possible penalties for China, although Trump will make any final determination.

In its report, the State Department also downgraded the Democratic Republic of Congo, Congo and Guinea, while Afghanistan, Ukraine, and Qatar, which Tillerson all said had stepped up efforts to combat human trafficking, were upgraded.

Meanwhile, also present for Tillerson Tuesday’s announcement was Ivanka Trump, the president’s daughter and aide, who has taken on as part of her portfolio efforts to fight human trafficking.

“Ending human trafficking is a major foreign policy priority for the Trump administration,” Ivanka Trump said in brief remarks.

Her comments echoed those made by her father, who in February had pledged to put the “full force and weight” of the federal government to combat human trafficking.

The same month Trump signed an executive order designed to help crack down on “transnational criminal organizations” that engage in human trafficking. He also ordered the Justice Department and Department of Homeland Security to assess how they can better address human trafficking.