What happened to the divisor in the equation ?

If you are looking for a percentage change, the dividers cancel each other and hence are not essential.

The divisor is only used when a stock(s) have a stock split/reverse split that effects there price, so the divisor is adjusted to counteract the effect to keep the index consistent.

remember that value weighted indexes also have divisors

Is part of this LOS that we need to evaluate/calculate or just know the differences? For calculating Price-Weighted, we just assume 1 share of each stock and divide by the # of stocks correct? I’m going blank on how to do the others… frig, time to go back and review.