function romanize(num) {
    var lookup = {M:1000,CM:900,D:500,CD:400,C:100,XC:90,L:50,XL:40,X:10,IX:9,V:5,IV:4,I:1},
	roman = '',
	    i;
	for ( i in lookup ) {
	    while ( num >= lookup[i] ) {
		roman += i;
		num -= lookup[i];
	    }
	}
	return roman;
 }

function changeYear(year){
    myYear=document.getElementById(year).innerHTML;

    myYear=romanize(myYear);

    document.getElementById(year).innerHTML = myYear;
}