Much of that loss is due to the devastation following Hurricane Katrina in 2005.
"Census workers counted 343,829 residents in New Orleans last year, down from 485,000 in 2000, or a 29% drop, according to the data. The count was slightly lower than previous estimates of 355,000.
The city has struggled to repopulate since Hurricane Katrina and a breach of federal levees flooded 80% of the city in 2005, scattering much of its citizenry. Just before the storm, there were about 455,000 people living in New Orleans, according to Census figures."