Shell element thickness distribution

Hello everyone,

I am trying to assign a constant thickness value on the centroid of each shell element using the element distribution option. For this reason, and using an analytical/mapped field, I created a txt file with the x,y,z coordinates (location) and the field value (thickness) and then inserted in the distribution table of Abaqus. The coordinates I introduced correspond to the center of each element (element type S4R).  

However, the values are not assigned correctly on each element when I read the generated input file. Does anyoone have an idea on the issue??