I don't know this particular company's methodology but, in a nutshell, usually they consider a number of glide paths and then run Monte Carlo simulations for each, then choose the best performing one. The goal is to minimize the probability of running out of money before dying, assuming the retiree withdraws a constant amount every year. Some studies concluded that a rising-equity path performs better.

Of course it's more complicated than that. There's a lot of assumptions embedded in those simulations: life expectancy, bonds and stocks returns, etc. See below for more info.

The Case for Increasing Stock Exposure in Retirement https://www.aier.org/research/case-increasing-stock-exposure...

Reducing Retirement Risk with a Rising Equity Glide Path https://www.onefpa.org/journal/Pages/Reducing%20Retirement%2...

That's interesting, because increasing the percentage of equities over time is literally the opposite of what most other investment advice sources preach. Thanks for the links. :)

Hi! Kai here from True Link. #1 lesson from the launch so far is that graph is totally incomprehensible! We love it here in the office but it's going to be totally re-done in the next release.

That graph is how your money is invested today – we divide your money up based on what age you need it and invest it differently, so what the graph is saying is that "money you need for age 61" is 90% in cash, and "money you need for age 86" is 85% in equities.

People are so used to seeing the glide path graph that like half of people see our graph and are like, wow that's incredibly smart, and half are like, your glide path is upside down.

Also, probably didn't help that I cropped out the axis labels so it would fit nicer on Medium. Thanks for noticing! I'm going to fix that right now.

As it happens, our glide path in aggregate ends up within conventional bounds – we have a screen in the tool that compares the equity percentages to what you'd have in a Vanguard or T Rowe Price target date fund and usually it's in the same ballpark.