Link to the study:

https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2767066

"Between 2000-2002 and 2016-2018, the proportion of 18- to 24-year-old individuals who reported having had no sexual activity in the past year increased among men (18.9% vs 30.9%) but not among women (15.1% vs 19.1%)"