What is the difference between Wholesale and Consumer in 2019? 
{"Operating revenue -- International and Global Accounts": {"2019": 3596, "2018": 3653, "2017": 1382}, "Operating revenue -- Enterprise": {"2019": 6133, "2018": 6133, "2017": 4186}, "Operating revenue -- Small and Medium Business": {"2019": 2956, "2018": 3144, "2017": 2418}, "Operating revenue -- Wholesale": {"2019": 4074, "2018": 4397, "2017": 3026}, "Operating revenue -- Consumer": {"2019": 5642, "2018": 6116, "2017": 6451}, "Operating revenue -- Total segment revenue": {"2019": 22401, "2018": 23443, "2017": 17463}, "Operating revenue -- Operations and Other(1)": {"2019": "\u2014", "2018": "\u2014", "2017": 193}, "Operating revenue -- Total operating revenue": {"2019": 22401, "2018": 23443, "2017": 17656}}
consumer_2019 = df["Operating revenue -- Consumer"]["2019"]
wholesale_2019 = df["Operating revenue -- Wholesale"]["2019"]
answer = consumer_2019 - wholesale_2019