Swicth() / case difficulty

The following expression aims at setting the value of a Tumble  parameter according to a choice from a dropdown menu expression controller. The dropdown menu does make its way to  the "xx" variable. The swicth doesn't work. I am not getting an error from the expressio parser.  The variable "jjj" remains stuck on its initialized value. Any ideas?  Thanks ahead for any clues!

var xx = thisComp.layer("OFFSET").effect("FLIP MODE")("Menu");
var jjj = 0
switch(xx){
case 1: jjj =0; break;
case 2: jjj =10; break;
case 3: jjj =30; break;
case 4: jjj =50; break;
case 5: jjj =90; break;
case 6: jjj =130; break;
case 7: jjj =180; break;}
jjj;