It's a question that is so difficult to answer. It's not like having a cold-you can't simply wake up with an anxiety disorder because you forgot to wash your hands before eating. Anxiety disorders are forged over years of experiences. They have a genetic component, an upbringing component, an environmental component.
The Missouri Office of Administration recently released new population projections for Missouri and its counties. Missouri's population is expected to approach 6.8 million people in 2030, a growth of roughly 1.2 million people from the year 2000, which will represent a 21% increase in the state's population.
Places (incorporated), 1900-1990. Dynamic mapping of the Missouri population, 1810 to 2010 (Now with 2010 data!) Mapping of the Missouri minority population, 1810 to 2010. See these and other (entire U.S.) historical animations from the links at http://mcdc-maps.missouri.edu/.