Explanation
In this example, the goal is to return a number that represents quarter (i.e.
1,2,3,4) for any given date.
In other words, we want to return the quarter that the date resides in.
In this case, because we want to get back an integer, we use zero fornum_digits.
Unlike standard rounding, where only numbers less than 5 are rounded down, ROUNDUP roundsall numbers up….
