The Texas growth spurt isn't slowing.The state had eight of the 15 fastest-growing large cities and six of the 15 cities with the largest numeric increases between April 1, 2010, and July 1, 2011, according to Census figures released Thursday. Fort Worth recorded the 12th largest numeric increase, adding 16,708 residents for a total of 758,738, according to population estimates by the U.S. Census Bureau. Its the same story for Texas. Were growing faster than any other state and the major urban areas are driving that growth, said state demographer Lloyd Potter.New York City added the most people (69,777) followed by Houston (45,717), San Antonio (32,152), Austin (30,221) and Los Angeles (27,077). Dallas (25,413) was ranked sixth. and El Paso (16,416) was 13th."These numbers provide further evidence of a continuation of the trend of rapid population growth in Texas we observed between the 2000 and 2010 censuses, Census Bureau director Robert Groves said. Fort Worth retained its ranking as the nations 16th largest city while Austin edged past San Francisco for the No. 13 spot. Other Texas cities on that top 20 list are No. 4 Houston, No. 7 San Antonio, No. 9 Dallas and No. 19 El Paso. Demographer Steve Murdock of Rice University said the continuation of rapid growth in Texas is no surprise."Its very much to be expected. But the fact that it hasnt slowed down surprises me a little bit. Its very robust growth, he said.Although Texas dominated the list of fastest-growing cities, New Orleans was ranked No. 1, growing by 4.9 percent to 360,740 or 79.2 percent of its pre-Hurricane Katrina population estimate of 455,188.At No. 2 was Round Rock, which grew by 4.8 percent, topping the 100,000 mark since the 2010 Census. Other Texas cities on the list fastest growers are Austin, Plano, McKinney, Frisco, Denton, McAllen and Carrollton.Nationally, the census data indicates that large cities grew faster than suburbs as the recession slowed migration to the outer rings of metropolitan areas.But that wasnt the case in Texas, where many suburbs were growing even faster than the urban areas they surround, demographers said. The big cities growth has somewhat slowed, but when you look at the cities and counties surrounding the metro areas, thats where the major growth is occurring, Potter said.That trend is illustrated by the list of the fastest-growing areas with a population of at least 50,000. Fourteen Texas towns are in the top 20, and all are adjacent to the states five biggest cities.Texas growth is being driven by migration, but it has been supplemented by a healthy rate of natural growth, Potter said.We have a relatively young population, which is increasingly Hispanic, and that population tends to have a higher birth rate, Potter said. Add migration to that, and you have why we are topping all these growth lists.Much of the migration stream has come from California, Arizona and Florida, all of which have been hit hard by the recession and the housing crisis, he said.The question is, will that inflow continue as the economy rebounds?Were starting to see that the housing markets are coming back across the country and that may stem it a little bit. As other areas recover from the recession it may slow the flow of migrants, Potter said.