JavaScript Ordinal Number Display

gistfile1.js

var ordinalNumberDisplay = function (number) {
    var suffixes = ["th", "st", "nd", "rd", "th", "th", "th", "th", "th", "th"];
    switch (number % 100) {
        case 11:
        case 12:
        case 13:
            return number + "th";
        default:
            return number + suffixes[number % 10];
    }
};

alert(ordinalNumberDisplay(33)); //Alerts '33rd'