Given the secretive nature of the Office of Naval Intelligence, and the confusing records of the Spartan-II Program, it is difficult to tally the total number of Spartans in service. Official records indicate that 75 were forcibly recruited in 2517, and that of them only 33 survived augmentation. Since then, until 2552, officially, only four Spartans have become "MIA," one retiring, and another too wounded to continue serving. However, there are discrepancies - Indigo Team is one of them.