Homelessness in Dallas County

Apparently volunteers in the city of Dallas conduct an annual 'homeless census', conducting a physical count  of the homeless in the streets of Dallas County. Here is a chart with the numbers of the homeless from the last eight years' counts.

(Click chart for larger view)

Today Dallas is conducting its count for 2011, and the data will be available in the Spring.

• I wonder what explains the low numbers in 2008. Could it have to do with a particularly bad weather on the day of the count?

Data from the Dallas Morning News article.