BOGOTA, Aug 31 (Reuters) - Colombia"s urban jobless rate fell to 15% in July from 24.7% in the same month last year, the government statistics agency said on Tuesday, based on surveys in the 13 biggest cities. The national unemployment rate was 14.3%, down from 20.2% a year earlier, the DANE agency said. The urban jobless rate is more closely watched by financial markets than the national figure. Nearly 70% of the workforce is in large cities. Unemployment figures are not seasonally adjusted and can be volatile, usually depending on factors like peak shopping periods and vacation months. For the full report go to: here Urban National Unemployment Unemployment July 15.0% 14.3% June 17.1% 14.4% May 16.6% 15.6% (Reporting by Bogota newsroom; editing by Jonathan Oatis) Our Standards: The Thomson Reuters Trust Principles.