"This apparent conflict between theory and empirical evidence poses a problem in determining the optimal role of exchange rates in the formation of appropriate economic policies. The proposition that flexible exchange rates lead to balance of payment equilibrium position primarily rests on the purchasing power parity theory." (Effects of Exchange Rate)
Mexico is one of the most important members when it comes to trading with the US and it is also one of the fastest developing economy. The Gross Domestic Product of the Mexican Economy was $574.5 billion in the year 2001 and the net value of the exports was approximately $178 billion. Mexico is one of the most important trading partners of the US and hence it is very important economically to the US. There has been many instances of Mexican-American dialogues recently and majority of these dialogues have been regarding strengthening the economic relationship between the two countries.
"Mexico's main exports are manufactured goods. These tend to be normal goods. An increase in demand will result in an increase in their consumption. Similar arguments are also applicable for the relation between Mexican Import and Mexican real GDP.