While there was a great deal of variation in the form that Inca bureaucracy and government took at the provincial level, the basic form of organization was decimal. In this system of organization, taxpayers—male heads of household of a certain age range—were organized into corvée labor units (which often doubled as military units) that formed the muscle of the state as part of mit'a service. Each level of jurisdiction above one hundred tax-payers was headed by a kuraka, while those heading smaller units were kamayuq, a lower, non-hereditary status. However, while kuraka status was hereditary, one's actual position within the hierarchy (which was typically served for life) was subject to change based upon the privileges of those above them in the hierarchy; a pachaka kuraka (see below) could be appointed to their position by a waranqa kuraka. Furthermore, it has been suggested that one kuraka in each decimal level also served as the head of one of the nine groups at a lower level, so that one pachaka kuraka might also be a waranqa kuraka, in effect directly responsible for one unit of 100 tax-payers and less directly responsible for nine other such units.