President Donald Trump's sliding-scale assessment of the effects of a trade war with China is wrong, The New York Times reported, refuting his assertion China has had its "worst year" in 57 years.

"China's gross domestic product grew 6.2% from April to June compared with a year earlier, the slowest rate since 1992" — 30 years short of what Trump touted — Times reporter Linda Qiu wrote.

She noted Trump correctly described China's slump in economic growth as the "worst in 27 years" July 20, and "at least four other times" before amending the numbers in August.

According to Qiu, Trump on Aug. 9 said China had experienced its worst year in 35 years. He changed that to 27 years Aug. 18 and increased it to 54 years Aug. 20, before declaring "it was actually 52 or 54 years" Aug. 21. He adjusted the estimate Aug. 23 to "anywhere from 30 to 50 years."

Last Friday, he expanded the number to 61 years.

• Trump: Dow Would Be 10,000 Points Higher Without Trade War
• Study: Trade War Will Cost at Least $460 Per Family