Why does China have to be broken down into 2 zones?

Anhui|Beijing|Chongqing|Fujian|Gansu|Guangdong|Guangxi|Guizhou|Hainan|Hebei|Heil ongjiang|Henan|Hubei|Hunan|Jiangsu|Jiangxi|Jilin|Liaoning|Nei Mongol|Ningxia|Qinghai|Shaanxi|Shandong|Shanghai|Shanxi|Sichuan|Tianjin|Xinjiang |Xizang (Tibet)|Yunnan|Zhejiang";