What was the percentage change in total goodwill in 2019 from 2018?
{"": {"2019 Goodwill": "\u00a3m", "2018 Goodwill": "\u00a3m"}, "Steam Specialties": {"2019 Goodwill": 113.0, "2018 Goodwill": 119.3}, "Electric Thermal Solutions": {"2019 Goodwill": 244.7, "2018 Goodwill": 183.0}, "Watson-Marlow": {"2019 Goodwill": 60.0, "2018 Goodwill": 65.7}, "Total goodwill": {"2019 Goodwill": 417.7, "2018 Goodwill": 368.0}}
total_goodwill_2019 = df["Total goodwill"]["2019 Goodwill"]
total_goodwill_2018 = df["Total goodwill"]["2018 Goodwill"]
answer = (total_goodwill_2019 - total_goodwill_2018) / total_goodwill_2018 * 100.0