9.8% royalty instead of 10%

[ZoeChapman]

Every now and again, I get a sale which comes through listed as a 9.8% royalty when the product is set at 10%.  For example, someone placed 9 separate orders last night for a total of 45 can coolers. The orders have come through with a mix of 10% and 9.8%.  

I have double checked my listings (as I have each can cooler size/shape also listed separately) and they are all set to 10%.  Anyone explain why this happens?  Guessing it has something to do with them selecting a difference size option, but I'd like to understand how it works.

(note: nothing to do with the third party deduction from my final royalty)

Thanks in advance!

[Sara_H]

@ZoeChapman it's down to the customer adding secondary content (ie one of the backgrounds from the Design Tool) and it goes to the designer that contributed that content I believe

https://help.zazzle.com/hc/en-us/articles/360039941013-Secondary-Content-FAQ

[ZoeChapman]

Thanks for clarifying Sara!