Another issue related to motives and preferences for saving is the role of the rich in generating aggregate saving. Do rich Americans account for most of U.S. saving? Not really. Relative to their incomes, some of the rich save a lot, and some dissave. So, too, for the poor. As Donald Trump will tell you, there is considerable mobility of wealth in the United States, at least over long periods of time (see Human Capital). The fact that the ranks of the rich are continually changing suggests that some of those who are initially rich dissave and dissipate their wealth, while others who are not initially rich save considerable sums and become rich.