My grandmother always made a similar dressing for just about everything. Since it came from her, of course there are no measurements.
Combine Miracle Whip (mayo if preferred), mustard, vinegar, sugar, celery salt & pepper. To thin it down, add a little milk. It's kind of "mix to taste" & if you end up with too much for your macaroni, you just toss it out. We always put in elbows, chopped carrot, hard boiled egg (diced) & pickle.
I stopped making that type a few years ago & do pasta salad instead now.
Pasta Salad
1 lb tri-colored screws
8 oz 3-bean salad
6 oz marinated artichoke hearts
8 oz Newmans Own Balsamic Vinaigrette
4 oz chickpeas, drained
For company or special occasions, I add:
½ bag frozen broccoli/cauliflower/carrot mix
4 oz pepperoni (cut slices into slivers)
1 c shredded mozzarella
¼ c Parmesan or Romano
4 oz black olive slices, drained
1 tomato, chopped
(No need to cook broccoli mix just defrost before adding. The crunch is a nice contrast to the pasta & by using the frozen its somewhat softer than fresh would be.)