Why are my numbers being imported to a PowerPivot Column as text?

[Stidd]

I have an excel table of data that contains fields that are definitely numerical values; there is no text in them except the header. Yet every time I create a linked table to PowerPivot is puts the field in as text column with a little warning sign that lets me create a calculated column (using some IFERROR and INT functions) to essentially replicate it as a numerical value or to leave it as text.As text, I obviously can’t do any calculations. I don’t really want to create all the calculated columns and am frustrated as I have no idea why it is doing it. Any help appreciated.