Quoted:

Probably.  If I'm reading it right, among people (groups of children and of adults) who received a pre-exposure prophylactic vaccination schedule (doses at zero and seven days) retained significant indicators of long-term effectiveness a year after vaccination and demonstrated test results indicating significant effectiveness 10-11 years after the initial vaccination without boosters.  These results are almost as good as a three dose series (days 0, 7, 21-28) in adults.  So I think you'd retain significant immunity for much longer.  But it's relatively easy and inexpensive to test and is commonly done, so if you're at any significant risk of exposure to rabies you should talk to a doctor about titer tests and boosters.

Edit and result: untreated rabies is 100% fatal, and many people in situations with elevated risk of exposure may be exposed in ways that are not obvious.  Rabies vaccines have been in use for well over a century, and modern vaccines for decades.  You're an idiot if you suspect exposure or are at increased risk of exposure and do not get a vaccination course.