This price check algorithm is KNOWN to be incorrect. It is most accurate for cheaper patterns where the float is field tested or close to field tested.
Please understand that this tool is meant to give you a VERY GENERAL price, and you should always consult the actual sale history for confirmation.
If no sale history is given for the pattern, or the float range you requested doesn't have a sale - the margin of error will be MUCH larger.
This algorithm will be most accurate when there are a lot of sale records for the item. Please consult the volume page to that regard.
Understand that you are using this tool by your own volition and risk.