The average median annual household income for all census block groups across Texas is roughly $55,200.It’s hard to say, specifically, which block group has the highest or lowest median household income on this map. The American Community Survey caps its median household income estimates at $250,000 or more on the high end, and $2,500 or less on the low end. There’s only one block group that reaches the low end of that scale, Block Group 1 in Waco, immediately adjacent to Baylor University. On the far distant side of that spectrum are a set of 30 block groups where the Census statisticians found median annual incomes of $250,000 or more.The lion’s share of those are scattered around Dallas and Houston, which many high-profile oil, gas and energy executives call home. Houston, in particular, has an obvious belt of suburban affluence that almost completely encircles a central city that, for the most part, lives on much more modest annual household earnings, with the significant exception being the ultra-wealthy areas immediately west of downtown Houston. And while Houston has a belt of affluence, Dallas could be said to have an affluence hat, with that city’s best-heeled neighborhoods