Slide in text

programming flash
1

I am tring to make some text slide in from the position x = 610 to x = 20

Heres my attempt at the AS for it (to proove i’m, not just being lazy):

 
onClipEvent(enterFrame) {
 speed = 5;
 this._x = 610;
 if (this._x > 20;) {
  this._x -= speed;
 }else{
  this._x = 20;
 }
}

What have i done wrong