What is the % change in the total revenue from 2018 to 2019?
{"Total revenues": {"2019": 2632.6, "2018": 2099.2}, "Pretax loss": {"2019": -157.5, "2018": -724.9}, "Net loss": {"2019": -200.1, "2018": -734.5}}
total_revenue_2019 = df["Total revenues"]["2019"]
total_revenue_2018 = df["Total revenues"]["2018"]
answer = ( ( total_revenue_2019 - total_revenue_2018 ) / total_revenue_2018 ) * 100.0