[Código Javascript] Dias Online de tu Web

<script>
var montharray=new Array("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec")
function countup(yr,m,d){
var today=new Date()
var todayy=today.getYear()
if (todayy < 1000)
todayy+=1900
var todaym=today.getMonth()
var todayd=today.getDate()
var todaystring=montharray[todaym]+" "+todayd+", "+todayy
var paststring=montharray[m-1]+" "+d+", "+yr
var difference=(Math.round((Date.parse(todaystring)-Date.parse(paststring))/(24*60*60*1000))*1)
difference+=" dias"
document.write("TuWeb.es.tl con "+difference+" dí­as Online!")
}
countup(día,mes,año)
</script>