What is the ethnic composition of the neighborhood in which you live?

[ag]

Well, I live in Mexico City, so you'd think it should be nearly 100% Hispanic, though, obviously, Mexican census doesn't collect such data. In fact, by the US definition of the term it, probably, is: almost all people here could claim to be Mexican. On the other hand, this has nothing to do w/ race: the most common ancestry, at least among the old-timers here is, probably, German (some local business names are Kafe Klatsch, Pateleria la Vienesa, Unser Kluv bar, etc.). So, how should we count that?

[ag]

Since about a quarter of the people here aren't even citizens (and thus won't be counted in any census)

The census is supposed to count all de facto residents: citizens, legal immigrants, illegal immigrants, temporary residents - everyone.  In 2000 I was counted as resident in NYC, even though I was on a non-immigrant (student) visa and was about to leave the country for good. In fact, I don't even remember them asking me about my residence status.