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There are over 4000 speakers of Tsum, known as Tsumpas. Many speakers of the language have migrated away from the Tsum valley, and now live in Kathmandu and abroad. Younger Tsumpas are more likely to be educated in Nepali and English, leading to attrition of the language.
There is a varying degree of mutual intelligibility between Tsum and other Kyirong-Yolmo varieties. It is most closely related to Nubri and Gyalsumdo, and more distantly related to other languages in the family.