The new gas pricing system and classification of subscribers in 4 levels of consumption The National Gas Company of Iran announced that according to the new pricing system, subscribers will be placed in 4 levels of consumption, and the cost of gas will be calculated step by step with the increase in consumption. About 70% of the subscribers are in a good consumption group and consume gas according to the established pattern. Also, 18% of the subscribers are in the second stage, 10% in the third stage and 2% in the fourth stage.