What was the percentage change in the Cumulative Consumer Accounts between 2017 and 2019?
{"Transaction Volume -- Dollars (in millions)": {"2019": 5954.0, "2018": 5030.0, "2017": 3767.0}, "Transaction Volume -- Percentage increase": {"2019": 18.0, "2018": 34.0, "2017": ""}, "Loan Servicing Portfolio -- Dollars (in millions, at end of period)": {"2019": 9150.0, "2018": 7341.0, "2017": 5390.0}, "Loan Servicing Portfolio -- Percentage increase": {"2019": 25.0, "2018": 36.0, "2017": ""}, "Active Merchants -- Number (at end of period)": {"2019": 17216.0, "2018": 14907.0, "2017": 10891.0}, "Active Merchants -- Percentage increase": {"2019": 15.0, "2018": 37.0, "2017": ""}, "Cumulative Consumer Accounts -- Number (in millions, at end of period)": {"2019": 3.03, "2018": 2.24, "2017": 1.57}, "Cumulative Consumer Accounts -- Percentage increase": {"2019": 35.0, "2018": 43.0, "2017": ""}}
cumulative_consumer_accounts_2019 = df["Cumulative Consumer Accounts -- Number (in millions, at end of period)"]["2019"]
cumulative_consumer_accounts_2017 = df["Cumulative Consumer Accounts -- Number (in millions, at end of period)"]["2017"]
answer = (cumulative_consumer_accounts_2019 - cumulative_consumer_accounts_2017) / cumulative_consumer_accounts_2017 * 100.0