What is the population of Nairobi?
Nairobi
{'answer_start': array([-1]), 'answer_text': array([''], dtype=object)}
Nairobi has experienced one of the highest growth rates of any city in Africa. Since its foundation in 1899, Nairobi has grown to become the second largest city in the African Great Lakes, despite being one of youngest cities in the region. The growth rate of Nairobi is currently 4.1% a year.[59] It is estimated that Nairobi's population will reach 5 million in 2025.[60]