я бы это сделал так:
<html>
<head>
<script language="javascript" type="text/javascript">
function checkYear() {
var archive = document.getElementsByName('Year')[0];
if (archive.length == 1) // вероятно нам не нужно заполнять повторно при клике.
{
var currDate = new Date();
var currYear = currDate.getFullYear();
constYear = 2006;
//var a = [];
//var i = 0;
var i = currYear - constYear;
while(constYear <= currYear) {
var a = constYear++;
var listYear = new Option(a, a, false, false);
archive.options[i--] = listYear;
}
}
}
</script>
</head>
<body>
<form action="list.asp" name="archive">
<select name="Year" onclick="checkYear();">
<option value="noValue" selected>Выберите год</option>
</select>
<form>
</body>
</html>