Rendering Particle System with varying emission rates

I am working on rendering bubbles that come from the player through a particle system at varying emission rates. Would mathf.InverseLerp be a good function for this? If so, I would alter the min/max emission rates, correct?

Would it look like the following:

var minrate = 0.1;
var maxrate = 10.0;
var rate = 0.5;

function Start() {
    // parameter is now 3 / 5
    var parameter : float = Mathf.InverseLerp(minrate, maxrate, rate);
}

You can just use Random.Range(minRate, maxRate); instead.