what should they read?
What intake you running?? Oem or CAi?
Ideally readings as close to 0% but some intakes if non oem may have fuel trim adjust upto 15%!! Typically like Forge Twintake
Evoms and ITG read around 5-6%
Oem around 0-2%
ITG intake, gti running KO4
If yours reads when you check block 32, you don't need to log it, just read what it says as its an accumulative figure over time. It will give you 2 different figures. Idle figures are as near to zero, certainly under 10% would be acceptable.
If its in the Teens, I would be looking at what's been spoken over, as it means the Ecu is over correcting the fuelling, or trying to compensate a fault that lies elsewhere.