"Efficiency levels" refers to how well or quickly something is being done or achieved. It measures how effectively resources are being used to produce desired results. Full definition
The high efficiency levels reported from labs often last only days or hours before the materials break down. (sciencenews.org)
I really thought it was nice when you said that food devoid of gluten is said to increase energy efficiency levels as well as promote the overall health and function of the digestive system. (forkoffgluten.com)
The results demonstrate that skilled and low - skilled readers often have different efficiency levels based on learning methods and reaction times. (gse.harvard.edu)