in this paper, we tested the catching up hypothesis toward USA using
Becker et al. (2006) flexible Fourier KPSS stationary test over the
period 1960-2009. The mentioned test could control for unknown
number and form of structural breaks using a selected frequency
component of a Fourier function. Our results show almost poor
countries stay poor and almost rich countries stay rich. South Korea,
Hong Kong, Singapore, Taiwan, India, Malaysia and China could
escape lag deadlock and the countries like Central African Republic,
Congo, Cote d`Ivoire, the Gambia, Guinea, Haiti, Kenya, Rwanda, and
Senegal diverged from USA and moved into poverty trap.