What was the percentage change in the total depreciation and amortization between 2018 and 2019?
{"Computer software": {"2019": 97.3, "2018": 94.5, "2017": 84.0}, "Other intangible assets": {"2019": 59.3, "2018": 57.2, "2017": 67.8}, "Deferred contract costs": {"2019": 42.9, "2018": 32.9, "2017": 25.7}, "Property and equipment": {"2019": 36.7, "2018": 32.4, "2017": 29.0}, "Total": {"2019": 236.2, "2018": 217.0, "2017": 206.5}}
total_2019 = df["Total"]["2019"]
total_2018 = df["Total"]["2018"]
answer = ( total_2019 - total_2018 ) / total_2018 * 100.0