What was the change in Additions in 2019 from 2018?
{"Cost: -- Balance as of 1 January": {"2019": 1886.3, "2018": 1726.6, "2017": 1697.4}, "Cost: -- Additions": {"2019": 81.3, "2018": 162.7, "2017": 103.1}, "Cost: -- Disposals": {"2019": -25.6, "2018": -30.2, "2017": -14.3}, "Cost: -- Transferred from prepayments": {"2019": 252.3, "2018": 81.8, "2017": "-"}, "Cost: -- Transferred to assets held for sale": {"2019": -130.1, "2018": -54.6, "2017": -59.6}, "Cost: -- Balance as of 31 December": {"2019": 2064.2, "2018": 1886.3, "2017": 1726.6}, "Depreciation: -- Balance as of 1 January": {"2019": 327.6, "2018": 264.8, "2017": 180.0}, "Depreciation: -- Disposals": {"2019": -25.6, "2018": -30.2, "2017": -14.3}, "Depreciation: -- Depreciation for the year": {"2019": 106.5, "2018": 113.4, "2017": 113.6}, "Depreciation: -- Transferred to assets held for sale": {"2019": -47.9, "2018": -20.4, "2017": -14.5}, "Depreciation: -- Balance as of 31 December": {"2019": 360.6, "2018": 327.6, "2017": 264.8}, "Impairment: -- Balance as of 1 January": {"2019": 162.1, "2018": 167.3, "2017": 173.6}, "Impairment: -- Impairment losses on tangible fixed assets": {"2019": 6.0, "2018": 3.2, "2017": 3.6}, "Impairment: -- Reversal of impairment ": {"2019": -120.0, "2018": "-", "2017": "-"}, "Impairment: -- Transferred to assets held for sale": {"2019": -19.3, "2018": -8.4, "2017": -9.9}, "Impairment: -- Balance as of 31 December": {"2019": 28.8, "2018": 162.1, "2017": 167.3}, "Impairment: -- Carrying amount as of 31 December": {"2019": 1674.8, "2018": 1396.6, "2017": 1294.5}}
cost_additions_2019 = df["Cost: -- Additions"]["2019"]
cost_additions_2018 = df["Cost: -- Additions"]["2018"]
answer = cost_additions_2019 - cost_additions_2018