Learn Russian: Объём рынка упал, и спрос стал в три раза меньше, чем раньше. - The market volume fell, and demand became three times smaller than before.

To express "X times more" or "X times less", Russian requires the preposition в followed by the Accusative case for the numeral. If you drop в and just say три раза, it means "three times" in terms of frequency (like "I checked it three times"), rather than a mathematical comparison.

Why is it раза here, but in other sentences I've seen раз?

The form of the word depends on the number. After 2, 3, and 4 (like три in this sentence), you use the genitive singular form раза. If the demand had shrunk by five times, you would use the genitive plural form required for numbers 5 and up: в пять раз меньше.

We are talking about demand falling. Could I use ниже instead of меньше?

Yes! In economic and business contexts, when talking about спрос (demand), объём (volume), or цены (prices), it is very natural to use ниже (lower). Using меньше (smaller/less) is also perfectly correct and is just slightly less formal.

Why must we use чем before раньше? Couldn't we just use the genitive case for the comparison?