What is the change in office equipment cost in 2019 and 2018?
{"Office equipment": {"2019": 38373, "2018": 39633}, "Furniture and fixtures": {"2019": 5017, "2018": 4610}, "Leasehold improvement": {"2019": 23534, "2018": 19430}, "Property and equipment, gross": {"2019": 66924, "2018": 63673}, "Less accumulated depreciation": {"2019": -44199, "2018": -49355}, "Property and equipment, net": {"2019": 22725, "2018": 14318}}
office_equipment_2018 = df["Office equipment"]["2018"]
office_equipment_2019 = df["Office equipment"]["2019"]
answer = office_equipment_2018 - office_equipment_2019