The locations of Federal Reserve District boundaries, and of the Banks within the Districts, were determined mostly by the geographic distribution of the U.S. population at the time the Federal Reserve System was created (1913), to accommodate local needs.
Mr Trump claims the total cost of the wall will be $10bn (Â£7.5bn) to $12bn. But estimates from fact checkers and engineers seem to be universally higher. Senate Majority Leader Mitch McConnell estimated it will cost between $12-15bn, as he addressed reporters at a Republican conference in Philadelphia.
âThe things Donald Trump has said are utterly unworkable,â Douglas Holtz-Eakin, an economic adviser to Senator John McCainâs 2008 presidential campaign and the forum's president, told Reuters. Trumpâs plan for a border wall could cost several billion dollars more.