Reverse this expression on Type

I folowed this ( https://www.youtube.com/watch?v=LRazU7uNgD0 ) tutorial which allowed me to get a really nice bouncy text animation using this expression:

freq = 1;
decay = 7;
duration = 0.10;
retard = textIndex*thisComp.frameDuration*2;
t = time - (inPoint + retard);
startVal = [100,100,100];endVal = [0,0,0];
if (t < duration){
linear(t,0,duration,startVal,endVal);
}else{
amp = (endVal - startVal)/duration;
w = freq*Math.PI*2;
endVal + amp*(Math.sin((t-duration)*w)/Math.exp(decay*(t-duration))/w);}

I wondered if it's possible to start the animation from the end of the text and not the start and speed up the animation.

I have attached an example below - I want the bottom line to start from the 'g' and go in just like the top line starts from the 'a' and goes in. 

Appreciate any input.