Efficiency analysis of Turkish natural gas distribution companies by using data envelopment analysis method

► In Turkish natural gas distribution sector, non-tender firms are more efficient. ► The most important reason of inefficiency is immaturity. ► Tender firms suffer from the immaturity and low penetration. ► The results of efficiency analysis should not be used by regulator in tariff setting. ► This study should be repeated after the immaturity problem is resolved.