Spreadsheet loader error "You need to enter a valid value for the RateObjectId attribute"

I am running a spreadsheet loader to update some grade rates, however for a small number I am getting the following error "You need to enter a valid value for the RateObjectId attribute. The current values are 0,ESB1.6/ILIN131." how to I resolve this?

Columns in my loader are:

Grade Rate Name	* Set Code	* Grade Code	* Legislative Data Group Name	* Effective Start Date	Minimum	Maximum	Midpoint