How to give table alternating row colors?

I read this article: http://articles.sitepoint.com/article/javascript-101-2

I want to Combine this example with the example given in Part 1 to give this table of revenues alternating row colors!

Here are my combining codes:
It is quite clear there must be something with them because I can’t see the expected result after running. Help me find that mistake. Thank you.

<html>
<head>

</head>

<body>

<script type=“text/javascript”>
<!–
var months = new Array(12);
months[0] = “January”;
months[1] = “February”;
months[2] = “March”;
months[3] = “April”;
months[4] = “March”;
months[5] = “June”;
months[6] = “July”;
months[7] = “August”;
months[8] = “September”;
months[9] = “October”;
months[10] = “November”;
months[11] = “December”;

var revenues = new Array(12233,43232,321445,23214,54546,342342,3425435,23423,65677,34223,54353,234233);
–>
</script>

<script type=“text/javascript”>
var color1 = “#6691BC”;
var color2 = “#769DC5”;
var rownumber=1;

function tablerow() {

var currentcolor;

if ( rownumber % 2 == 0 ) {
currentcolor=color1;
else {
currentcolor=color2;
}
}
document.write(“<tr bgcolor=”+currentcolor+“>”);
rownumber=rownumber+1;
}
</script>

<table border=“5”>
<tr>
<th>Month</th>
<th>Revenue(thousands of $)</th>
</tr>

<script type=“text/javascript”>

</script>

<script type=“text/javascript”>
for(i=0;i<months.length;i++){

tablerow();
document.write(“<td>”+months[i]+“</td>”);
document.write(“<td>”+revenues[i]+“</td></tr>”);
}
</script>

</table>

</body>
</html>

Try

<html>
<head>


<script type="text/javascript">
<!--
   var months = new Array(12);
   months[0] = "January";
   months[1] = "February";
   months[2] = "March";
   months[3] = "April";
   months[4] = "March";
   months[5] = "June";
   months[6] = "July";
   months[7] = "August";
   months[8] = "September";
   months[9] = "October";
   months[10] = "November";
   months[11] = "December";

   var revenues = new Array(12233,43232,321445,23214,54546,342342,3425435,23423,65677,34223,54353,234233);

   var color1 = "#6691BC";
   var color2 = "#769DC5";
   var rownumber=true;


function tablerow(i) {

   var currentcolor;

   currentcolor= rownumber ? color1 : color2;
   document.write("<tr bgcolor="+currentcolor+"><td>"+months[i]+"</td><td>"+revenues[i]+"</td></tr>");
   rownumber=!rownumber
}
// -->
</script>

</head>



<body>


<table border="5">
<tr>
<th>Month</th>
<th>Revenue(thousands of $)</th>
</tr>
<script type="text/javascript">
<!-- 
   for(i=0;i<months.length;i++){
      tablerow(i);
   }
// -->
</script>

</table>

</body>
</html>