interval congestion in commercial bank branch

Congestion is one of the main problems in economic issues. in fact, congestion is a wasteful step in the production process, where outputs decrease as a result of increasing inputs. in the economy, congestion is important because its elimination reduces the cost and also increases the output. therefore, there is a great benefit in identifying congestion and reducing it. since it is difficult to compute congestion for dmus with interval data, owing to the computational complexity of the existing methods, we first present a new method for computing congestion and then obtain congestion in the case of interval data. it is well known that if dea inputs and outputs are in the form of intervals, there will be an efficiency interval for each dmu. since we assume interval data in this paper, we obtain an interval for the amount of congestion possible in each dmu and prove that the interval indicates the upper and lower bounds of congestion for each dmu