What was the percentage change in the net total inventory between 2018 and 2019?
{"Raw materials": {"2019": 8921, "2018": 6396}, "Finished goods": {"2019": 25247, "2018": 16594}, "Total inventory, net": {"2019": 34168, "2018": 22990}}
total_inventory_net_2019 = df["Total inventory, net"]["2019"]
total_inventory_net_2018 = df["Total inventory, net"]["2018"]
answer = ( total_inventory_net_2019 - total_inventory_net_2018 ) / total_inventory_net_2018 * 100.0