看进来。。。

Today, Western sources estimate the number of J-20s built by the end of 2019 as around 50, a figure that likely also includes pre-production machines. Unconfirmed Chinese reports suggest that a production capacity of 48 aircraft annually, but there is no evidence that that figure has been attained.

https://www.thedrive.com/the-war-zone/38655/ten-years-ago-today-chinas-j-20-stealth-fighter-first-flew-a-two-seater-could-be-next