What was the percentage change in Industrial Solutions in 2019 from 2018?
{"Industrial Solutions": {"$  7,821": 3954, "58 %": 30, "$ 8,290": 3856, "59 %": 28}, "Communications Solutions": {"$  7,821": 1673, "58 %": 12, "$ 8,290": 1842, "59 %": 13}, "Total": {"$  7,821": 13448, "58 %": 100, "$ 8,290": 13988, "59 %": 100}}
industrial_solutions_2019 = df["Industrial Solutions"]["$  7,821"]
industrial_solutions_2018 = df["Industrial Solutions"]["$ 8,290"]
answer = ( industrial_solutions_2019 - industrial_solutions_2018 ) / industrial_solutions_2018 * 100.0