Setting up .csv file for mass sign

Hi, I am attempting to set up a .csv file to autofill certain aspects of a document for me upon sending to certain users. Is it required that the column name on the .csv file starts with "_es_signer"? How is the .csv file read by Adobe Sign and what determines the pretext to the field name?

Example:

I have a column "salary" in my .csv and in order to have it fill on send based on that column, I would need to name that field "salary". Would the column name "salary" in the .csv need to be "_es_signer_salary"?

Thank you.