var c_years = 0;
function set_year(yr){
    if(yr == -1) yr = "%";
    document.getElementById('ctl00_ctl00_cphBody_cphBody_hidYear').value = yr;
    __doPostBack(); 
}
function show_years(yrs){
    var tmp = document.getElementsByTagName("span");
    var year_sets = [];
    for(var i = 0; i < tmp.length; i++){
        if(tmp[i].className == "yrSet")
            year_sets.push(tmp[i]);
    }
    year_sets[c_years].style.display = "none";
    year_sets[yrs].style.display = "inline";
    c_years = yrs;
    if(c_years > 0)
        document.getElementById("yrPrev").style.display = "inline";
    else
        document.getElementById("yrPrev").style.display = "none";
    
    if(c_years < year_sets.length - 1)
        document.getElementById("yrNext").style.display = "inline";
    else
        document.getElementById("yrNext").style.display = "none";
    return false;        
}