I have the following JS code which creates a calculator, however the calculator isn't functioning properly. Only the last 2 commands for each set of outputs are working. Anyone know why?

function weightVolume(a) {

var outPut = '';
if(a <= 90) { outPut = '0-76'; }
if(a < 110) { outPut = '94-110'; }
if(a < 130) { outPut = '111-127'; }
if(a < 150) { outPut = '128-144'; }
if(a < 170) { outPut = '145-161'; }
if(a < 190) { outPut = '162-178'; }
if(a < 210) { outPut = '196-212'; }
if(a > 230) { outPut = '213-230'; }
document.getElementById("volume").innerHTML = outPut + ' Litres';

}

function heightWidth(a) {
var outPut = '';
if(a <= 60) { outPut = '30'; }
if(a <= 72) { outPut = '31-32'; }
if(a > 72) { outPut = '32'; }
document.getElementById("width").innerHTML = outPut + 'in';
}

function areaLength(a) {
var outPut = '';
if(a === "Cruising" ) { outPut = "10&rsquo;6 or 12&rsquo;"; }
if(a === "Surf" ) { outPut = "10&rsquo; or Less"; }
if(a === "Racing" ) { outPut = "12&rsquo; or More"; }
document.getElementById("area").innerHTML = outPut;
}