The first is Millenial as a whole, the second is Millenial broken down by age. Essentially, the oldest Millenials have a ~65% homeownership rate and Millenials as a whole have ~54%.
Sorry late reply. I believe the goal of separating by age is to have a more apples-to-apples comparison and to see trajectories. For instance, it highlights that at a young age, Gen Z is actually ahead of previous generations on homeownership, but also the upward slope looks like it may trend flatter. It isn't drastically different, in this case, than just looking at the averages.
I understand the goal of separating it by age, I'm confused by the methodology they would have used to calculate the data on the second chart and get to 65%.
It seems like you are saying they got to the 65% rate because it's a snapshot of homeownership % for "older millennials" in 2023. But that doesn't make sense because they also give data for 18 year old millennials.
I would have expected them to use the same lines in the 1st chart but change the X axis to be age of the cohort so that they start at the same pt.