Mexico City, Mexico - Last year I caught a glimpse of Mexico City's mostly ignored Occupy movement. I saw a few demonstrators camped out in front of the shimmering mirrored panels of the country's stock exchange. Only two young protesters sat in the tent in front of hand-written placards that displayed messages such as "THE OUTRAGED OF THE WORLD UNITE!" and "THE STATE CAN ONLY SUSTAIN ITSELF THROUGH CRIME."

One police officer watched from in front of the stock exchange while crowds of well-dressed young professionals walked by talking on Blackberries and iPhones. After surveying the scene, I wrote an article in which I explained "The problem for the Occupy movement is that even though Mexico continues to struggle with ongoing problems of inequality and poverty, in the last fifteen years, an unprecedented number of young Mexicans have joined the country's middle class."

Over the course of 2012's presidential election cycle and again in 2013 as Mexico's economy has slowed, the debate has continued about the size and dynamics of Mexico's middle class. According to a report from Mexico's National Institute of Statistics and Geography (INEGI) Mexico's elite upper class includes 1,340,000 people or 1.7 percent of all the country's inhabitants.

By contrast, the country's lower class includes 66.4 million residents, who collectively represent 59.1 percent of the country's total population. To put this in perspective, for every upper class person in Mexico there are 49 in the lower class.

In 2013 Mexico's upper income segment is pushing growth in the higher-end retail market. One recent report by Reuters' Alex Alper and Elinor Comlay explained "Sales at department stores Palacio de Hierro and Liverpool rose about 10 percent in the first quarter from the year earlier, almost double revenue growth at supermarket chains Wal-Mart de Mexico and Soriana over the same period."

Overall, the INEGI study found that the middle class in Mexico includes 39.2 percent (44 million people) of the country's total population. Mexico's middle class increased 11.4 percent during between 2000 and 2010.

As I explained in an earlier post about Chiapas, a wide income gap persists between urban and rural areas in Mexico. While nearly half of all urban residents are members of the middle class, only slightly more than a quarter of Mexico's rural residents enjoy this distinction. Although pockets of poverty persist in parts of many major Mexican metropolises, the worst poverty in the country is still found in the hills of southern states such as Guerrero, Oaxaca, and Chiapas.

Although flatscreen TV and cellular phone ownership and other indicators on the rise, the diagnosis for the health of Mexico's middle class isn't exactly clear. One study found that Mexico's young professional "dual income no kids" couples collectively spend nearly US$20 billion per year on non-essential items. Another report found that Mexico's luxury goods market is likely to grow by 12 percent this year.

Overall, in 2012 Mexicans spent nearly $4 billion on luxury apparel, up from just $2 billion in 2004. Franco Calderon, the president of the Latin American Retail Connection, a retail sector market research and market entry consultancy, explained "We see a definite uptick in interest from brands that just a couple of years ago we never imagined would be calling us and saying, 'We're interested in Latin America and what can you tell us about Mexico?'"

More broadly, however, retail sales in Mexico grew by less than 4 percent in 2012.

According to a recent article by political scientist Mario Arriagada for Mexican news magazine Nexos, "the expansion of the 'global middle class' is a popular theme right now. The majority of the planet is still notably poor, but there's a part of the population in emerging economies that increasing its income rapidly."

In Mexico, between 1992 and 2000 most households saw their income levels stagnate or even fall. Even during this period marked by the start of NAFTA, the tequila crisis, and multiple recessions, however, Mexico's upper middle class saw it's income grow by double digits. The country's lower middle class also saw a jump in income.

Mexico's middle class, however, has not fared as well as the country's billionaires. According to a Forbes report, in 2013 "Carlos Slim from Mexico clocked in with a net worth $4 billion more than a year ago and is the world's richest man for the fourth year in a row, with a fortune of $73 billion."

In 2012 Slim's America Movil telecom company reported total revenues of $62 billion, a 6 percent jump from 2011. The company added more than 1 million cell phone customers in Mexico during the course of the year. Total, there are 99 billionaires from Latin America and 15 Mexican billionaires, according to Forbes' analysis.

While nearly three quarters of the residents in Mexico's countryside have sub-middle class income levels, 3 of the top 5 wealthiest individuals in Latin America are from Mexico. Alberto Bailleres Gonzalez the chairman and partial owner of Industrias Peñoles, is the second wealthiest man in both Mexico and Latin America. Forbes estimates his net worth at $18.2 billion.

German Larrea Mota Velasco, the owner of mining giant Grupo Mexico, a company that reported net income of over $2 billion last year, is Mexico's third wealthiest businessman, and the fifth wealthiest man in Latin America. Forbes estimates his net worth at $16.7 billion USD.

According to the latest INEGI study, most middle-income Mexican families haven't had the same success as the country's billionaires over the last few years. While Mexico's top income decile saw its income jump 4.5 percent between 2010 and 2012 as the country's economy rebounded from the global financial crisis, many middle-income families saw their household income drop.

Although Mexico's middle class does appear to be growing and consumer goods and luxury goods sales are rising it's important to remember that many middle-class families actually saw their household incomes fall over the past two years.

The country's president, Enrique Peña Nieto, campaigned on the simple promise "You'll Earn More," and has pledged to significantly increase GDP growth. While the upper income bracket continues to fare relatively well, robust economic growth will depend on the inclusion of a broader segment of the country's population in modern Mexico's success.

Mario Arriagada explained, "In the first decade of the twenty-first century the expansion of household income of the middle class [in Mexico] has been greater that what happened in the previous decade. However, this expansion has not been sufficient. The Mexican middle class can't do it on its own and needs help to complete its supposed manifest destiny."