Merged Column Header

Hi All,

I want to merge two cells to have one column Header (not the values in 2 columns) using Power BI. I have the rawdata in excel that has the column header merged together but when I bring the data in power bi desktop, table doesnt look like same anymore - I want to have the result like the picture below (Mexico as the column Header and have Target and Annual as two columns under it)-

Appreciate your help