What is the percentage change of the Audit fees from 2017 to 2018?
{"": {"2017": "(In Thousands)", "2018": "(In Thousands)"}, "Audit Fees (1)": {"2017": 3747, "2018": 4476}, "Audit-Related Fees (2)": {"2017": "\u2014", "2018": "\u2014"}, "Tax Fees (3)": {"2017": "\u2014", "2018": "\u2014"}, "All Other Fees (4)": {"2017": 3, "2018": 3}, "Total Fees": {"2017": 3750, "2018": 4479}}
audit_fees_2018 = df["Audit Fees (1)"]["2018"]
audit_fees_2017 = df["Audit Fees (1)"]["2017"]
answer = (audit_fees_2018 - audit_fees_2017) / audit_fees_2017 * 100.0