Some cities always have been and always will be booming metropolises. But along with these, which include New York City, San Francisco, and Seattle, others are making their way up the population charts to become a contender. Still others are going the opposite direction.Damian Schmidt of Iristorm Design made this infographic called “The Fastest- and Slowest-Growing Metropolitan Areas in the U.S.” It consists of a map of the United States pinpointed with cities that have the fastest-growing populations, as well as those where the population is declining. It is color-coded, as explained in a key on the right side. It specifies which areas the population is rapidly declining or increasing, as well as those where the change is gradual but steady.