sentences:  Demand for cigars increased after World War II, but by that time, almost all of Ybor City's cigar factories were mechanized and did not re-hire the skilled and well-paid artisans they had once employed by the thousands.As veterans returned from the war, they largely chose to leave the aging neighborhood for areas with better housing and economic prospects, accelerating the trend of declining population and economic contraction.This process accelerated further through the 1950s and 60s, when the federal Urban Renewal program and the construction of Interstate 4 resulted in the demolition of many structures, including hundreds of housing units.