Drilling rig efficiency unit per month (DREupm) is a key indicator to display drilling productivity. The major factors are determined from a lot and analyzed to boost DREupm. This paper, based on the fuzzy relevancy theory, relates the practical data, analyzes the efficiency per hour, waiting ratio and working ratio, and concludes that working ratio is the primary factor to DREupm, and then the efficiency per hour and waiting ratio, offering a reference for drilling management.
