According to the U.S. Census, there were 20.6 million Mexican Americans in 2000. They made up 7.3 percent of the total U.S. population of 281 million people and 58.5 percent of the total Hispanic American population of 35.3 million. Mexican Americans are the fastest growing ethnic group in the nation. They have a high birth rate compared with other U.S. ethnic groups, causing a rapid population increase. But recent immigration has also greatly increased the population of Mexican Americans. There were about 7.9 million foreign-born Mexican Americans in 2000, and Mexico is the country of origin of the largest number of recent immigrants, contributing 27.7 percent of the total number of foreign-born residents of the United States in 2000. Hispanic Americans are considered the second largest ancestry group in the nation (after German Americans). If Latino groups are considered individually, however, Mexican Americans form the fifth largest ancestry group in the nation...