In case you missed it earlier today, the Geforce 531.18 driver which was released on February 28 had this issue where users noticed a 10 to 15 percent CPU usage from Nvidia driver. Nvidia manager, Sean Pelletier, promised that the hotfix will be coming soon, and now it is ready for download.
The driver is pretty much based on the previous Geforce 531.18 driver, so it comes with all those same game optimizations and bug fixes, but also fixes the new high CPU usage from Nvidia Container after exiting a game.
It also fixes a random bugcheck that was spotted on some laptops with GTX 10/MX250/350 series GPUs.
You can find the Geforce 531.26 Hotfix driver over at Nvidia's support page.