It's the ability of a guy hired four years ago to hold different seats and an estimate of when he can hold seats currently above his seniority.
As retirements increase those time periods should reduce. In the last four yrs roughly 1950 known retirements were forecast. In the next fours years it's about 2950-3000. Basically that shifts all of the data points I posted about a year sooner for a late 2018 new hire vs a late 2014 new hire. The large increase in retirements is throwing some of the old rules of thumb, at least in the short term, out the window. Guys getting hired now will initially have faster advancement than the guys hired four years ago. But obviously the guys hired four years ago will always be ahead of them.
The junior CA seniority dropped over a 605 numbers in a year after adjusting for the seniority change. Basically the same number as retirements. Which means I screwed up the projected CA upgrade date. It's more like 6 yrs +/- a month instead of 5 yrs and a month.
The increase is retirements will make future advancements quicker until the upgrade time is past the peak retirement years. I'd guess the cross-over estimate for that is 2019-2020 for new hires. Instead of having a 5 yr upgrade they'll revert to six years, then seven, etc. Looking at the difference between the bottom guy and the junior CA and it's about 3700 numbers. So a guy hired in five years (2023) is still looking at about 7 yrs to advance 3700 numbers. That's for the junior guy and most won't take that opportunity so their upgrade time will be longer. But it will be nothing like the last decade when it reached 17 yrs +/-.