Mexico City consists up to 21.5% ($390 billion) of the country’s GDP as well as being the industrial sector. The unemployment in the city is as low as 4.9%. Due to the economic boom, Mexico City became the epicenter for migrants from Southern regions to seek work, bringing the total population to over 19.5 million people. Combination of work opportunities and expansion has greatly urbanized Mexico City since the 1930s, but the largest population growth occurred between 1990-2000 when the population almost doubled from 10 million to 18 million. Researchers stated that there are over 25.7 million people working in Mexico City that aren’t documented.
Source:
Here is a video showing photos from various parts of Mexico City combined with some interesting facts on the city.
[Source]