What was the percentage change in total transactions from 2018 to 2019?
{"Management and administrative services revenue": {"2019": 5904, "2018": 6167, "2017": 5711}, "Ship management fees income": {"2019": 1210, "2018": 1400, "2017": 824}, "Debt guarantee compensation (i)": {"2019": 693, "2018": 861, "2017": 775}, "Other (ii)": {"2019": -2, "2018": -247, "2017": 135}, "Total": {"2019": 7805, "2018": 8181, "2017": 7445}}
total_2019 = df["Total"]["2019"]
total_2018 = df["Total"]["2018"]
answer = ( total_2019 - total_2018 ) / total_2018 * 100.0