What was the change in gross profit between 2017 and 2018?
{"Net revenue": {"2019": 25282320.0, "2018": 22095416.0, "2017": 19063121.0}, "Gross profit": {"2019": 1913401.0, "2018": 1706792.0, "2017": 1545643.0}, "Operating income": {"2019": 701356.0, "2018": 542153.0, "2017": 410230.0}, "Net income attributable to Jabil Inc": {"2019": 287111.0, "2018": 86330.0, "2017": 129090.0}, "Earnings per share  basic": {"2019": 1.85, "2018": 0.5, "2017": 0.71}, "Earnings per share  diluted": {"2019": 1.81, "2018": 0.49, "2017": 0.69}}
gross_profit_2018 = df["Gross profit"]["2018"]
gross_profit_2017 = df["Gross profit"]["2017"]
answer = gross_profit_2018 - gross_profit_2017