Volorf

// Don't forget to assing parent to a layer with the expression
delay = .1;
parent.fromWorld(toWorld(anchorPoint,time-delay))

Volorf

// Source — https://www.motionscript.com/design-guide/looping-wiggle.html

freq = 1;
amp = 100;
loopTime = 3;     // Set loop time for 3 sec.
t = time % loopTime;
wiggle1 = wiggle(freq, amp, 1, 0.5, t);
wiggle2 = wiggle(freq, amp, 1, 0.5, t - loopTime);
linear(t, 0,  loopTime, wiggle1, wiggle2)

Volorf

// Initial and last frames of an animation. 
var startKeyFrame = 30;
var endKeyFrame = 50;
// Initial and final values of a text layer.
var startValue = 500;
var endValue = 1000;

// Util vars for a calc function
var currentFrame = time/thisComp.frameDuration, 
    deltaKeyFrames = endKeyFrame - startKeyFrame,