The percentages of FY 1999 active duty NPS accessions in each AFQT category are shown in Table 2.8. The percentage of recruits in Categories I and II was approximately the same as their civilian counterparts (males - 39 versus 39 percent; females - 34 versus 33 percent). Category III accessions greatly exceeded civilian proportions (males - 61 versus 30 percent; females - 66 versus 37 percent), while the percentage of recruits in Category IV was much lower than in the civilian population (males - 1 percent versus 20 percent; females - less than 1 percent versus 22 percent). The low percentage of Category IV recruits is, in part, a result of DoD limits of 4 percent Category IV recruits, with even lower Service limits. Ten percent of civilian males and 9 percent of civilian females scored in Category V; DoD allows no Category V recruits.

It is critical to know how ASVAB scores are calculated and what they are used for.  The Armed Services Vocational Aptitude Battery (ASVAB) tests are used to identify whether a candidate is qualified to enlist in a particular branch of the U.S. Military.  The ASVAB test is also used to determine which military jobs (referred to as MOS for Military Occupational Specialties) a candidate is best suited for.  ASVAB scores can also be used by test takers to help explore which careers they may be a good fit for them – whether they go into the military or not. While no one officially passes or fails the ASVAB, each branch of the military has specific minimum scores required for enlistment.  Your scores also affect the type of military job, enlistment bonuses and salary you are eligible for.
One ASVAB sub-measure, the Armed Forces Qualification Test (AFQT)--which is just a separate analysis of the same tests that focuses only on four of the subtests--is also population-referenced, but its score from 1-99 is a percentile score. This means that if you score a 73, you scored as well as or higher than 73% of test-takers in the national sample.