The percentage of poor in Manhattan is much lower than in rural areas, or even in Brooklyn, even if you adjust for cost of living.
Of course it's lower than in Brooklyn; but that's not exactly hard. But in Manhatten 17.6% of families live below the poverty line (2000 Census). Compared with 9.2% nationally. That's rather high.
But here's the problem in Manhatten; in 2000 as much as 9% of households earned over $200,000 a year. Meanwhile, as much as 14% earned under $10,000.
That depends how you define wealthy doesn't it?
Surrey is certainly the wealthiest county in England. There are a few pockets which can't be described as wealthy o/c (though that's really all they are; pockets) and some areas are richer than others. But it's not really comparable with, say, Manhatten as far as this goes. A better comparision would be with somewhere like Islington; which has one of the highest average wages in the U.K, but some of the highest IMD (ie; deprivation) figures also.