And make sure to discount inflation. While we haven’t had inflation the last many years (so they say) costs are very likely to rise before retirement.
Be careful about assuming expenses are less during retirement - it really depends on the lifestyle you want. I don’t spend really any money during the day besides lunch... I’m working, what can I buy? While when I retired there’s tons of projects I can fund or traveling excursions I’m interested in. That, and healthcare is the ultimate unknown!