Output:

 # zpool status 
   ... 
  scan: scrub in progress since Sun Jul 25 16:07:49 2021 
      403M scanned at 100M/s, 68.4M issued at 10.0M/s, 405M total 
      0B repaired, 16.91% done, 00:00:04 to go 

Where:

Metadata which references 403M of file data has been scanned at 100M/s, and 68.4M of that file data has been scrubbed sequentially at 10.0M/s.