Leave it. It's just a nice check every month for the rest of the life as soon as you hit the magic number. I left teaching and at the ripe age of 58ish I will continue working my current job and will just get a bonus check of 3k a month. That means I get to live better in my later working years than I ever did in my younger working years with no stress. Plus, it is there for the rest of my life. At this point of your career, (21 years means mid to late 40's), just let it sit.