What was the percentage change in segment operating income before income tax expense between 2017 and 2018?
{"Reconciliation to consolidated net revenues: -- Segment net revenues": {"2019": 5969, "2018": 6835, "2017": 6765}, "Reconciliation to consolidated net revenues: -- Revenues from non-reportable segments (1)": {"2019": 462, "2018": 480, "2017": 410}, "Reconciliation to consolidated net revenues: -- Net effect from recognition (deferral) of deferred net revenues (2)": {"2019": 101, "2018": 238, "2017": -139}, "Reconciliation to consolidated net revenues: -- Elimination of intersegment revenues (3)": {"2019": -43, "2018": -53, "2017": -19}, "Reconciliation to consolidated net revenues: -- Consolidated net revenues": {"2019": 6489, "2018": 7500, "2017": 7017}, "Reconciliation to consolidated income before income tax expense: -- Segment operating income": {"2019": 2054, "2018": 2446, "2017": 2417}, "Reconciliation to consolidated income before income tax expense: -- Operating income (loss) from non-reportable segments (1)": {"2019": 24, "2018": 31, "2017": -19}, "Reconciliation to consolidated income before income tax expense: -- Net effect from recognition (deferral) of deferred net revenues and related cost of revenues (2)": {"2019": 52, "2018": 100, "2017": -71}, "Reconciliation to consolidated income before income tax expense: -- Share-based compensation expense": {"2019": -166, "2018": -209, "2017": -178}, "Reconciliation to consolidated income before income tax expense: -- Amortization of intangible assets": {"2019": -203, "2018": -370, "2017": -757}, "Reconciliation to consolidated income before income tax expense: -- Fees and other expenses related to the acquisition of King (4)": {"2019": "\u2014", "2018": "\u2014", "2017": -15}, "Reconciliation to consolidated income before income tax expense: -- Restructuring costs (5)": {"2019": -137, "2018": -10, "2017": -15}, "Reconciliation to consolidated income before income tax expense: -- Other non-cash charges (6)": {"2019": "\u2014", "2018": "\u2014", "2017": -14}, "Reconciliation to consolidated income before income tax expense: -- Discrete tax-related items (7)": {"2019": -17, "2018": "\u2014", "2017": -39}, "Reconciliation to consolidated income before income tax expense: -- Consolidated operating income": {"2019": 1607, "2018": 1988, "2017": 1309}, "Reconciliation to consolidated income before income tax expense: -- Interest and other expense (income), net": {"2019": -26, "2018": 71, "2017": 146}, "Reconciliation to consolidated income before income tax expense: -- Loss on extinguishment of debt": {"2019": "\u2014", "2018": 40, "2017": 12}, "Reconciliation to consolidated income before income tax expense: -- Consolidated income before income tax expense": {"2019": 1633, "2018": 1877, "2017": 1151}}
segment_operating_income_2018 = df["Reconciliation to consolidated income before income tax expense: -- Segment operating income"]["2018"]
segment_operating_income_2017 = df["Reconciliation to consolidated income before income tax expense: -- Segment operating income"]["2017"]
answer = ( segment_operating_income_2018 - segment_operating_income_2017 ) / segment_operating_income_2017 * 100.0