Optimization for the Locations of Ambulances under Two-Stage Life Rescue in the Emergency Medical Service: A Case Study in Shanghai, China

Table 1

Distribution of calls from January 1 to December 31, 2013.

Scenario	Day time	Day type	Badly injured	General injury	Demand count	Proportion
1	Dawn	Workdays	192	1560	1752	9.0%
2	Morning	Workdays	469	3734	4203	21.6%
3	Afternoon	Workdays	411	3463	3874	19.9%
4	Evening	Workdays	395	3243	3638	18.7%
5	Dawn	Off-days	79	815	894	4.6%
6	Morning	Off-days	189	1446	1752	8.4%
7	Afternoon	Off-days	240	1522	1762	9.1%
8	Evening	Off-days	164	1525	1689	8.7%
Total			2139	17308	19447	100%