Give at least three reasons why tracking the informal sector of an economy is difficult.

Unofficial earning strategies (illegality in business): (1) Unofficial business activities: tax evasion, avoidance of labor regulation and other government or institutional regulations, no registration of the company; and (2) Underground activities: crime, corruption - activities not registered by statistical offices. 

Travel clerkdegree level: certificate or college degree preferred by employersdegree field: travel planning, travel, or tourism licensure and certification: business license may be required; voluntary certifications available construction carpenterrequired education: a high school dimploma and carpentry apprenticeship transportation managerdegree level: bachelor's degree in supply chain management or bachelor's degree in logistics degree field: supply chain management, systems engineering and business licence or certification: no legal requirement for a transportation to become certified but is recommended since certifications demonstrate commitment to excellence and a broader knowledge chief executive degree level: bachelor's degree; mba preferred degree field: liberal arts, business administration, public administration or field of specialty chosen (i.e health care administration)license or certificate: voluntary certification available