Works correctly for me on the command line in 2012. Difficult to remedy without seeing the code you using.
Command: (progn
(_> (setq alist '("1/2" "1/2" "ldct1.sld" 89.00 60.30 15.80 4 11.20 21.30 48.00 00.60) Countr 0)
(_> (repeat (length alist) (print (nth Countr alist)) (setq Countr (1+ Countr)))
(_> (princ)
(_> )
"1/2"
"1/2"
"ldct1.sld"
89.0
60.3
15.8
4
11.2
21.3
48.0
0.6