What is the percentage change in long-term debt in 2019?
{"Debt due within one year": {"2019": 3881, "2018": 4645}, "Long-term debt": {"2019": 22415, "2018": 19760}, "50% of outstanding preferred shares": {"2019": 2002, "2018": 2002}, "Cash and cash equivalents": {"2019": -145, "2018": -425}, "Net debt": {"2019": 28153, "2018": 25982}}
longterm_debt_2019 = df["Long-term debt"]["2019"]
longterm_debt_2018 = df["Long-term debt"]["2018"]
answer = ( longterm_debt_2019 - longterm_debt_2018 ) / longterm_debt_2018 * 100.0