What was the change in issued capital in 2019 from 2018?
{"SELECTED FINANCIAL DATA: IFRS --  millions, unless otherwise stated": {"2019": 2019.0, "2018": 2018.0, "2017": 2017.0, "2016": 2016.0, "2015": 2015.0}, "Income Statement Data: Years ended December 31, -- Cloud revenue": {"2019": 6933.0, "2018": 4993.0, "2017": 3769.0, "2016": 2993.0, "2015": 2286.0}, "Income Statement Data: Years ended December 31, -- Software licenses and support revenue": {"2019": 16080.0, "2018": 15628.0, "2017": 15780.0, "2016": 15431.0, "2015": 14928.0}, "Income Statement Data: Years ended December 31, -- Cloud and software revenue": {"2019": 23012.0, "2018": 20622.0, "2017": 19549.0, "2016": 18424.0, "2015": 17214.0}, "Income Statement Data: Years ended December 31, -- Total revenue": {"2019": 27553.0, "2018": 24708.0, "2017": 23461.0, "2016": 22062.0, "2015": 20793.0}, "Income Statement Data: Years ended December 31, -- Operating profit": {"2019": 4473.0, "2018": 5703.0, "2017": 4877.0, "2016": 5135.0, "2015": 4252.0}, "Income Statement Data: Years ended December 31, -- Profit after tax": {"2019": 3370.0, "2018": 4088.0, "2017": 4046.0, "2016": 3629.0, "2015": 3056.0}, "Income Statement Data: Years ended December 31, -- Profit attributable to owners of parent": {"2019": 3321.0, "2018": 4083.0, "2017": 4008.0, "2016": 3642.0, "2015": 3064.0}, "Earnings per share(1) -- Basic in ": {"2019": 2.78, "2018": 3.42, "2017": 3.35, "2016": 3.04, "2015": 2.56}, "Earnings per share(1) -- Diluted in ": {"2019": 2.78, "2018": 3.42, "2017": 3.35, "2016": 3.04, "2015": 2.56}, "Weighted-average number of shares outstanding -- Basic": {"2019": 1194.0, "2018": 1194.0, "2017": 1197.0, "2016": 1198.0, "2015": 1197.0}, "Weighted-average number of shares outstanding -- Diluted": {"2019": 1194.0, "2018": 1194.0, "2017": 1198.0, "2016": 1199.0, "2015": 1198.0}, "Statement of Financial Position Data: At December 31, -- Cash and cash equivalents": {"2019": 5314.0, "2018": 8627.0, "2017": 4011.0, "2016": 3702.0, "2015": 3411.0}, "Statement of Financial Position Data: At December 31, -- Total assets": {"2019": 60215.0, "2018": 51502.0, "2017": 42484.0, "2016": 44262.0, "2015": 41390.0}, "Statement of Financial Position Data: At December 31, -- Current financial liabilities(2)": {"2019": 3273.0, "2018": 1125.0, "2017": 1561.0, "2016": 1813.0, "2015": 841.0}, "Statement of Financial Position Data: At December 31, -- Non-current financial liabilities(2)": {"2019": 12923.0, "2018": 10553.0, "2017": 5034.0, "2016": 6481.0, "2015": 8681.0}, "Statement of Financial Position Data: At December 31, -- Issued capital": {"2019": 1229.0, "2018": 1229.0, "2017": 1229.0, "2016": 1229.0, "2015": 1229.0}, "Statement of Financial Position Data: At December 31, -- Total equity": {"2019": 30822.0, "2018": 28877.0, "2017": 25515.0, "2016": 26382.0, "2015": 23295.0}}
issued_capital_2019 = df["Statement of Financial Position Data: At December 31, -- Issued capital"]["2019"]
issued_capital_2018 = df["Statement of Financial Position Data: At December 31, -- Issued capital"]["2018"]
answer = issued_capital_2019 - issued_capital_2018