US Census says the 1990 population was 159789 and the 2000 population was 158216. Your 2006 estimate may or may not be accurate therefore it is not factual. I did misquote about the school enrollment as it has been decreasing since 1970 when there were 35,000 students and in 2006 there were 22,947.
http://www.al.com/specialreport/hunt...gain/sa11.html
http://factfinder.census.gov/servlet...rd=&_industry=
I would guess that without large annexation, the population would have stayed stable or decreased since 2000.
The lack of maintenance of the existing infrastructure and minimal road improvement was also due to the requirements of providing same for new development. The existing customers of the city pay higher use rates for power , water and garbage because of the costs of providing these services to the new developments.