Analysts see this more than 7 percent increase in the number of drivers as a manifestation of the subdued job market.
At least four others have issued warnings of overcapacity, with some saying drivers get fewer than 10 orders a day as a result.
Cai said he earns 200-300 yuan a day, driving for Didi Global - China's answer to Uber - from 8.00 am until close to midnight.
Up until recently, he made 400 yuan a day plus bonuses, going home before 8.00 pm.
Shanghai driver Li Weimin's rationale for working underscores the shrinking job market.
Persons:
Zhu Zhimin, Zhu, Wang Ke, James Cai, Cai, Didi, Wang, Nanxun Li, It's, Li, Casey Hall, Xihao Jiang, Marius Zaharia
Organizations:
Transport, Thomson
Locations:
SHANGHAI, Shanghai, China, Cities, Sanya, Changsha, Haikou, Hainan, Analysys, Beijing