What is the percentage change in the revenue from agricultural, commercial and industrial group from 2018 to 2019?
{"Agricultural, Commercial, and Industrial (ACI)": {"2019": 28940, "2018": 33193}, "Public Works": {"2019": 12128, "2018": 17986}, "Residential": {"2019": 18762, "2018": 19786}, "Total": {"2019": 59830, "2018": 70965}}
revenue_2019 = df["Agricultural, Commercial, and Industrial (ACI)"]["2019"]
revenue_2018 = df["Agricultural, Commercial, and Industrial (ACI)"]["2018"]
answer = (revenue_2019 - revenue_2018) / revenue_2018 * 100.0