The chemical industry comprises the companies that produce industrial chemicals. Central to the modern world economy, it converts raw materials (oil, natural gas, air, water, metals, and minerals) into more than 70,000 different products. The plastics industry contains some overlap, as most chemical companies produce plastic as well as other chemicals. Various professionals are deeply involved in the chemical industry including chemical engineers, scientists, lab chemists, technicians, etc. As of 2018, the chemical industry comprises approximately 15% of the US manufacturing economic sector.