What is the year-on-year percentage change in cash flow from operations from 2018 to 2019?
{"For the fiscal year: -- Net revenue": {"2019 (1)": 2569.8, "2018": 2056.6, "2017": 2031.0, "2016": 2504.1, "2015": 2512.2}, "For the fiscal year: -- (Loss) income from operations": {"2019 (1)": -25.0, "2018": -509.1, "2017": -499.6, "2016": 1.3, "2015": 120.7}, "For the fiscal year: -- Net (loss) income": {"2019 (1)": -80.8, "2018": -566.9, "2017": -582.1, "2016": -330.5, "2015": 81.8}, "For the fiscal year: -- Cash flow from operations": {"2019 (1)": 377.1, "2018": 0.9, "2017": 169.7, "2016": 414.0, "2015": 708.6}, "Common stock data: -- Basic net (loss) income per share": {"2019 (1)": -0.37, "2018": -2.58, "2017": -2.61, "2016": -1.46, "2015": 0.36}, "Common stock data: -- Diluted net (loss) income per share": {"2019 (1)": -0.37, "2018": -2.58, "2017": -2.61, "2016": -1.46, "2015": 0.35}, "At year end: -- Total assets": {"2019 (1)": 4729.2, "2018": 4113.6, "2017": 4798.1, "2016": 5515.3, "2015": 4909.7}, "At year end: -- Long-term liabilities": {"2019 (1)": 2638.9, "2018": 2246.4, "2017": 1879.1, "2016": 2304.7, "2015": 1290.4}, "At year end: -- Stockholders (deficit) equity": {"2019 (1)": -210.9, "2018": -256.0, "2017": 733.6, "2016": 1619.6, "2015": 2219.2}}
cash_flow_2019 = df["For the fiscal year: -- Cash flow from operations"]["2019 (1)"]
cash_flow_2018 = df["For the fiscal year: -- Cash flow from operations"]["2018"]
answer = (cash_flow_2019 - cash_flow_2018) / cash_flow_2018 * 100.0