 The 1994 economic crisis in Mexico, subsequent to the start of the North American Free Trade Agreement (NAFTA), was associated with widespread poverty and a lower valuation for the peso relative to the dollar.It also marked the start of a massive swell in Mexican immigration, in which net illegal migration to the US increased every year from the mid-1990s until the mid-2000s.There are also examples where natural disasters and overpopulation can amplify poverty-driven migration flows.