How much are you currently contributing per year? That multiple includes both growth and futures contributions. Let’s say on your current salaries you’re saving 20% pre-tax (so $36k a year) That brings you to $350k before any growth. If we assume a 5% average growth factor over the next 5 years compounding (not guaranteed) along with that $36k/year, you should have $415k. If it grows at 7%, you’d have $445k. As you make more, you’ll also likely be able to set aside a larger percentage of your salary to retirement, so there’s variables involved but yeah $510 isn’t out of the realm of possibility