Do you want it to just go in a smooth curve from 0 to 100 and than back to 0?
in that case, usa i sinus curve. Like this:
Math.sin(time*Math.PI*2)*50+50
The Math.PI*2 tells it to do one loop in one second. Change this value to change the speed of this.
If you just want it to scale up to 100 and then jump back to 0, just write:
time*25%100
change “25” to change the speed