Delta shaped openness: Visualizing the foreign capital in mainland China/

Opening to the world is considered to be an important reason for China's rapid rise in recent decades. Due to China's unique geographical pattern, the eastern coastal areas have always been the window of China's interaction with the world. Although China's east-west openness gap has been widely recognized, mapping the huge gap is valuable in terms of recognizing mainland China. Foreign direct investment (FDI) reflects the long-term cooperative relationship between China and overseas, and FDI is deemed to show a high level of openness to the outside world. Based on the actual utilized amount of FDI capital of the prefecture-level cities in mainland China in 2016, this study developed an equal FDI capital map. The Yangtze River Delta (YRD) and the Pearl River Delta (PRD) are transformed into two much larger deltas, while non-delta-shaped regional units, including Beijing–Tianjin–Hebei (BTH), Fujian, Shandong, and Liaoning are also transformed into deltas of different scales. In addition, the distribution of FDI growth rates indicates that delta-shaped openness is being further strengthened in mainland China.