The extraordinary demands of the Punic Wars, in addition to a shortage of manpower, exposed the tactical weaknesses of the manipular legion, at least in the short term. In 217 BC, Rome was forced to effectively ignore its long-standing principle that its soldiers must be both citizens and property owners when slaves were pressed into naval service; around 213 BC, the property requirement was reduced from 11,000 to 4,000 asses. Since the Romans are unlikely to have preferred to employ slaves over poor citizens in their armies, it must be assumed that, at this point, the "proletarii" of the poorest citizens must also have been pressed into service despite their lack of legal qualification. By 123 BC, the financial requirement for military service was slashed again from 4,000 asses to just 1,500 asses. By this time, therefore, it is clear that many of the property-less former "proletarii" had been nominally admitted into the "adsidui".