Random array

Have put this together but the return value is not what I exspected.
Basically I want one of the four array objects to be randomised.

the_Dates = [“1993”, “1992”, “2000”, “1992”];

onEnterFrame = function(){
var Randoniser = (Math.random(the_Dates.length));
trace(Randoniser);
}

[COLOR=DarkRed]return in the trace
1993
2000
1992
2000
1993
2000[/COLOR]
(or something like that)

I know its my syntax and probably the methods i have used that are in appropriate.