What is the Total interest expense for years 2017-2019?
{"Interest expense on our various debt instruments: -- Term Loan A due July 2017(1)": {"2019": "$ \u2014", "2018": "$ \u2014", "2017": 3.6}, "Interest expense on our various debt instruments: -- Term Loan A due July 2022(2)": {"2019": 6.8, "2018": "\u2014", "2017": "\u2014"}, "Interest expense on our various debt instruments: -- Term Loan A due July 2023(3)": {"2019": 8.5, "2018": 8.9, "2017": 18.6}, "Interest expense on our various debt instruments: -- Revolving credit facility due July 2023(3)": {"2019": 1.4, "2018": 1.9, "2017": 2.4}, "Interest expense on our various debt instruments: -- 6.50% Senior Notes due December 2020(4)": {"2019": 25.4, "2018": 28.1, "2017": 28.1}, "Interest expense on our various debt instruments: -- 4.875% Senior Notes due December 2022": {"2019": 21.5, "2018": 21.5, "2017": 21.5}, "Interest expense on our various debt instruments: -- 5.25% Senior Notes due April 2023": {"2019": 23.1, "2018": 23.1, "2017": 23.0}, "Interest expense on our various debt instruments: -- 4.50% Senior Notes due September 2023": {"2019": 20.7, "2018": 21.8, "2017": 21.0}, "Interest expense on our various debt instruments: -- 5.125% Senior Notes due December 2024": {"2019": 22.4, "2018": 22.4, "2017": 22.3}, "Interest expense on our various debt instruments: -- 5.50% Senior Notes due September 2025": {"2019": 22.4, "2018": 22.4, "2017": 22.3}, "Interest expense on our various debt instruments: -- 4.00% Senior Notes due December 2027(4)": {"2019": 1.7, "2018": "\u2014", "2017": "\u2014"}, "Interest expense on our various debt instruments: -- 6.875% Senior Notes due July 2033": {"2019": 31.1, "2018": 31.0, "2017": 31.0}, "Interest expense on our various debt instruments: -- Other interest expense": {"2019": 19.4, "2018": 18.2, "2017": 18.3}, "Interest expense on our various debt instruments: -- Less: capitalized interest": {"2019": -8.4, "2018": -6.3, "2017": -10.3}, "Interest expense on our various debt instruments: -- Less: interest income": {"2019": -11.9, "2018": -15.1, "2017": -17.6}, "Interest expense on our various debt instruments: -- Total": {"2019": 184.1, "2018": 177.9, "2017": 184.2}}
interest_2019 = df["Interest expense on our various debt instruments: -- Total"]["2019"]
interest_2018 = df["Interest expense on our various debt instruments: -- Total"]["2018"]
interest_2017 = df["Interest expense on our various debt instruments: -- Total"]["2017"]
answer = interest_2019 + interest_2018 + interest_2017