India: Estimated population of 1.42 billion, making it the second-most populous country in the world.
China: Estimated population of 1.43 billion, the most populous country in the world.
Afghanistan: Estimated population of 41.2 million.
Iran: Estimated population of 85.2 million.
Tajikistan: Estimated population of 10.1 million.
Turkmenistan: Estimated population of 6.1 million.