What is the percentage change in leasehold improvements from 2018 to 2019?
{"Land and land improvements": {"2019": 7348, "2018": 13132}, "Buildings and improvements": {"2019": 48191, "2018": 57959}, "Machinery and other equipment": {"2019": 107297, "2018": 81727}, "Software": {"2019": 108526, "2018": 84631}, "Leasehold improvements": {"2019": 17064, "2018": 11991}, "Construction and internal-use software development in progress": {"2019": 16814, "2018": 12888}, "Accumulated depreciation and amortization": {"2019": -160271, "2018": -144782}, "": {"2019": 144969, "2018": 117546}}
leasehold_improvements_2019 = df["Leasehold improvements"]["2019"]
leasehold_improvements_2018 = df["Leasehold improvements"]["2018"]
answer = (leasehold_improvements_2019 - leasehold_improvements_2018) / leasehold_improvements_2018 * 100.0