The monthly amount of an RRB pension is determined by a complicated process involving an individual's accumulate earnings over his/her/its RR career and an average of the five highest earns years (which do not have to be consecutive). As with all pensions, RRB, SSI, and otherwise, whether you can survive on the monthly check depends on your spending habits. If you spend money like a drunken sailor, no, if you're prudent, like not buying the latest snazzy new automobile every year, yes.