Gabriel alberto Agudelo Instituto Tecnológico Metropolitano   Calle 40 No. 101A - 165 Medellín, Antioquia 05003 Colombia   albertoagudelo@itm.edu.co   www.itm,edu.co           JEL Areas: G3 : Corporate Finance and Governance: General G1 : General Financial Markets: General (includes Measurement and Data)