Survey on Human Resources in Science and Technology Self-assessment of the employed doctorate-holders Degree of relationship between the doctoral studies, by field of the doctoral studies, and the main job, at 31 December 2009. Units: percentage ;Total;High;Medium;Low; Total;100.00;63.62;20.50;15.89; Natural Sciences;33.49;22.52;6.29;4.69; Engineering and Technology;8.10;5.55;1.44;1.10; Medical Sciences;21.16;9.93;5.92;5.32; Agricultural Sciences;2.96;1.89;0.47;0.60; Social Sciences;20.15;15.12;3.54;1.49; Humanities;14.13;8.60;2.85;2.68; Notes: Source: National Statistics Institute