What was the percentage change in the Total cash and cash equivalent in 2019 from 2018?
{"": {"31 March 2019": "$M", "31 March 2018": "$M"}, "Cash at bank and in hand": {"31 March 2019": 134.3, "31 March 2018": 67.2}, "Short-term deposits": {"31 March 2019": 37.8, "31 March 2018": 52.8}, "Total cash and cash equivalent": {"31 March 2019": 172.1, "31 March 2018": 120.0}}
total_cash_2019 = df["Total cash and cash equivalent"]["31 March 2019"]
total_cash_2018 = df["Total cash and cash equivalent"]["31 March 2018"]
answer = (total_cash_2019 - total_cash_2018) / total_cash_2018 * 100.0