Scroll Bar Help

Question

I've attached the code that I created for using a scroll bar.. When you click to scroll and go back up to the top it doesn't go all the way up to the top..It goes a few lines down still.  How can I adjust this to be correct?
import caurina.transitions.*;
laminatetxt_mc.mask = scrollmask_mc
var yOffset:Number;
var yMin:Number = 0;
var yMax:Number = scrollbar_mc.track_mc.height - scrollbar_mc.handle_mc.height;
scrollbar_mc.handle_mc.addEventListener(MouseEvent.MOUSE_DOWN, handleDown);
stage.addEventListener(MouseEvent.MOUSE_UP, handleUp);
function handleDown(e:MouseEvent):void
stage.addEventListener(MouseEvent.MOUSE_MOVE, handleMove);
yOffset = mouseY - scrollbar_mc.handle_mc.y;
function handleUp(e:MouseEvent):void
stage.removeEventListener(MouseEvent.MOUSE_MOVE, handleMove);
function handleMove(e:MouseEvent):void
scrollbar_mc.handle_mc.y = mouseY - yOffset;
if(scrollbar_mc.handle_mc.y <= yMin)
scrollbar_mc.handle_mc.y = yMin;
if(scrollbar_mc.handle_mc.y >= yMax)
   scrollbar_mc.handle_mc.y = yMax;
   var scrollpercent:Number = scrollbar_mc.handle_mc.y / yMax;
   Tweener.addTween(laminatetxt_mc, {y:(-scrollpercent*(laminatetxt_mc.height-scrollmask_mc.height)), time:1});
e.updateAfterEvent();

Answer 1

import caurina.transitions.*;
laminatetxt_mc.mask = scrollmask_mc
var yOffset:Number;
var yMin:Number = 0;  // set minimum handle_mc y
var yMax:Number = scrollbar_mc.track_mc.height - scrollbar_mc.handle_mc.height; // set max handle_mc.y
scrollbar_mc.handle_mc.addEventListener(MouseEvent.MOUSE_DOWN, handleDown);
stage.addEventListener(MouseEvent.MOUSE_UP, handleUp);
function handleDown(e:MouseEvent):void
stage.addEventListener(MouseEvent.MOUSE_MOVE, handleMove);
yOffset = mouseY - scrollbar_mc.handle_mc.y;
function handleUp(e:MouseEvent):void
stage.removeEventListener(MouseEvent.MOUSE_MOVE, handleMove);
function handleMove(e:MouseEvent):void
scrollbar_mc.handle_mc.y = mouseY - yOffset;
if(scrollbar_mc.handle_mc.y <= yMin)
scrollbar_mc.handle_mc.y = yMin;
if(scrollbar_mc.handle_mc.y >= yMax)
   scrollbar_mc.handle_mc.y = yMax;
var n:Number = scrollbar_mc.m*scrollbar_mc.handle_mc.y+scrollbar_mc.b;
   Tweener.addTween(laminatetxt_mc, {y:n, time:1});
e.updateAfterEvent();
// the following assigns the parameters needed to scroll correctly.
paramF(scrollbar_mc,yMin,scrollmask_mc.y,yMax,scrollmask_mc.y-laminatetxt_mc.hei ght+scrollmask_mc.height);
function paramF(mc:MovieClip,x1:Number,y1:Number,x2:Number,y2:Number):void{
    mc.m = (y1-y2)/(x1-x2);
    mc.b = y1 - mc.m*x1;