What is the increase/ (decrease) in Net operating cash flows from Year Ended December 31, 2019 to December 31, 2018?
{"": {"Year Ended December 31,": 2019, "": 2018}, "Net operating cash flows": {"Year Ended December 31,": 383306, "": 182135}, "Net financing cash flows": {"Year Ended December 31,": -382229, "": 434786}, "Net investing cash flows": {"Year Ended December 31,": -50391, "": -663456}}
net_operating_2019 = df["Net operating cash flows"]["Year Ended December 31,"]
net_operating_2018 = df["Net operating cash flows"][""]
answer = net_operating_2019 - net_operating_2018