Houston is one of 4 fastest growing cities in US.

In a growth economy, we will expect vacancy rate going up since more people are opt to buy houses instead of renting.  We will expect this will be the trend in the cities with healthy economy.  Starting from 2009, we can see the rental vacancy going up.  This will put pressure on rental markets around the country.  The rent increase will slow down.  It is a good news for the renters, not so much to the landlords.