In recent years, a certain American version of democracy has deepened the suffering of people in the U.S. instead of improving their well-being, according to a report released by a Chinese think tank in Beijing on Monday.

Titled "Ten Questions for American Democracy," the report has been released by the Chongyang Institute for Financial Studies of the Renmin University of China.

A survey of 163 countries in 2020 showed that only three countries, including the U.S., saw a decline in the Social Progress Index in the past decade, the report said, adding that the U.S. experienced the sharpest drop in its index, which takes into account factors such as personal safety, health and K-12 education.

Additionally, the poor population in U.S. has remained above 30 million since 1990 and the poverty rate above 10 percent, said the report, citing data from Statista, a German company specializing in market and consumer data.

Citing data from Pew Research Center, the report showed that the middle-income class in the U.S. decreased from 61 percent of the population in 1971 to 51 percent in 2019, while during the same period, the population of the low-income class increased from 25 percent to 29 percent. Besides, the medium household wealth in 2016 was worse than that in 1998.

Meanwhile, the proportion of wealth owned by the richest 1 percent increased from 23.6 percent in 1989 to 32.3 percent by mid-2021, said the report, citing the Federal Reserve data. 

The Federal Reserve data also showed that as of the second quarter of 2021, the richest 1 percent had about $43.27 trillion in wealth, exceeding the bottom 90 percent of Americans and 14.3 times that of the bottom 50 percent.