4666
The city became the 4th - largest in the nation in 1920 , after only New York City , Chicago and Philadelphia with the influence of the booming auto industry .
 New York City, Chicago, Philadelphia
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 New York City, Chicago, Philadelphia