When did Mexico de-value the peso?

Answer 1

When the 1973 Oil Crisis hit the developed world, Mexican Presidents Luis Echeverria and Jose Lopez Portillo began to rely heavily on oil exports to support the financial needs of the country, taking advantage of the high oil prices. When the market eventually stabilized, the little diversification of exports resulted in an economic slump and a devaluation of the Peso by 500%. This is often called the Lost Decade or Decada Perdida(1973-1982).