Population figures for the city are inexact for Spaniards, mixed-race castas, and indigenous. Some idea of the indigenous can be discerned from tribute records. In 1525, the city had perhaps 22,000 indigenous inhabitants, dropping precipitously starting around 1550. A figure for Tenochtitlan tributaries in 1562 is 12,971.Gibson, The Aztecs Under Spanish Rule, figure 17, p. 379; Appendix 4, 460–462. The estimates of the European population in Mexico City is also imprecise, with figures coming from a variety of sources. In 1525 there were 150 households occupied by Spaniards, with the European population increasing steadily during the entire colonial period. The highest estimate for the colonial era is by Alexander von Humboldt, who estimated ca. 1802 that there were 67,500 whites in Mexico City.Gibson, Aztecs Under Spanish Rule, table 27 "Estimates of the White Population in Mexico City", p. 381.
