What is the change in Software between 2018 and 2019?
{"Software": {"2019": 114674, "2018": 170327}, "Buildings": {"2019": 92092, "2018": 64263}, "Equipment": {"2019": 60661, "2018": 100421}, "Furniture and fixtures": {"2019": 34768, "2018": 38200}, "Lease hold improvements": {"2019": 33668, "2018": 26319}, "Land": {"2019": 31374, "2018": 5124}, "": {"2019": 367237, "2018": 404654}, "Accumulated depreciation and amortization": {"2019": -236330, "2018": -331700}, "Property and equipment, net": {"2019": 130907, "2018": 72954}}
software_2019 = df["Software"]["2019"]
software_2018 = df["Software"]["2018"]
answer = software_2019 - software_2018