JS动画效果不能正常显示，大神帮忙看下

<!DOCTYPE html>
<html>
<head>
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
    <script> 
        $(document).ready(function () {
           
            var _totalJackpot = $('#gameTicker').text();/*获取网页中的值*/
            var _startsum = Math.round((_totalJackpot * 0.9995) * 100) / 100;
            var _offset = _totalJackpot - _startsum;                           /*两者之间的差值，没什么用*/
                               //调用函数，期望实现动画效果，为什么不行呢？
            function wajticker(_jstart, _jtotal) {
                var jstarts;
                if (_jstart < _jtotal) {                    var jstarts = _jstart + 0.01;
                }
                else {
                    jstarts = Math.round((_jtotal * 0.9995) * 100) / 100;
                }
               var displayVal = addCommas(Math.abs(Math.round(_jstart * 100) / 100));
               
                $('#sicTick').text('$' + displayVal);
               setTimeout(function () { wajticker(jstarts, _jtotal); }, 500);
            }            function addCommas(nStr) {
                nStr += '';
                x = nStr.split('.');
                x1 = x[0];
                x2 = x.length > 1 ? '.' + x[1] : '';
                var rgx = /(\d+)(\d{3})/;
                while (rgx.test(x1)) {
                    x1 = x1.replace(rgx, '$1' + ',' + '$2');
               }
               return x1 + x2;
            }
           // setInterval(wajticker(_startsum, _totalJackpot), 500);
            wajticker(_startsum, _totalJackpot);
        });
    </script>
</head>
<body>
    <div id="sicTick">
    </div>
    <div id="gameTicker" style="">11482710.20</div>
</body>
</html>试试吧，不知道是不是你要的结果