 Guadalajara again experienced substantial growth after the 1930s, and the first industrial park was established in 1947.Its population surpassed one million in 1964, and by the 1970s it was Mexico's second-largest city and the largest in western Mexico.Most of the modern city's urbanization took place between the 1940s and the 1980s, with the population doubling every ten years until it stood at 2.5 million in 1980.