At the time of the 2001 census, persons aged between 0 and 15 years comprised 16.1% of Žirmūnai's population, the second lowest percentage among Vilnius' elderates, slightly higher than Viršuliškės at 15.5%. However, it is likely that the average age of Žirmūnai's residents has decreased since the last census, and will continue to decrease, as a result of the active construction of new dwellings, which are acquired primarily by younger people. As housing prices rise, retirees are motivated to sell their apartments with the goal of acquiring cheaper housing elsewhere with funds to spare.