What was the percentage change in the work-in-process between 2018 and 2019?
{"Raw materials": {"2019": 577545, "2018": 579377}, "Work-in-process ": {"2019": 49315, "2018": 102337}, "Finished goods ": {"2019": 74078, "2018": 112632}, "Total inventories, net": {"2019": 700938, "2018": 794346}}
work_in_process_2019 = df["Work-in-process "]["2019"]
work_in_process_2018 = df["Work-in-process "]["2018"]
answer = (work_in_process_2019 - work_in_process_2018) / work_in_process_2018 * 100.0