In 2019 Millennials will turn 23 - 38 years old. In the next five years they will be 28-43. If I want to see the five-year projection of the total millennials in 2024, do I use the same age group 23-38 in 2019 for 2024 or do I use the age group 28-43 in 2024? I noticed when I did the latter the total projection number was lower than the 2019 number.
2019 Ages 23-38
2024 Ages 23-38
OR
2024 Ages 28-43
Which 2024 projection age is the correct one to use?