Sonaji grew very slowly during the Tiwanaku Period. Sector D has a population index value of 429 (7.5 ha), as opposed to 368 for the LF2 Sector C. This is an annual growth rate of only 0.02%, well below the phase average. Judging by the fancy Tiwanaku ceramics present on the surface of the site, as well as from evidence of Tiwanaku Period monumental construction, it would seem that Sonaji continues to serve as the locus of public ritual and perhaps elite habitation for the Santa Rosa group (T-271/T-272/T-322; see sections 7.2.1 and 7.2.2).
The Santa Rosa group as a whole grew from a population index value of 1435 for the LF2 to 1959 for the Tiwanaku Period. This is an annual growth rate of only 0.05% again below the phase average of 0.08% (Table 8.1). Thus the Tiwanaku Period settlement system as a whole evidences a reduced importance of the largest sites on the peninsula, and higher relative growth in the lower tiers of the hierarchy. This in turn indicates a transformation of the political economy, as will be discussed at more length later in this chapter.