What was the change in total lease asset between January and December?
{"Assets -- Right of use lease assets": {"Classification": "Other Assets", "December 31, 2019": 8452, "January 1, 2019 (1)": 10322}, "Assets -- Total lease asset": {"Classification": "", "December 31, 2019": 8452, "January 1, 2019 (1)": 10322}, "Liabilities -- Current lease liability": {"Classification": "Accrued expenses", "December 31, 2019": 2676, "January 1, 2019 (1)": 2948}, "Liabilities -- Non-current lease liability": {"Classification": "Other non-current liabilities", "December 31, 2019": 5818, "January 1, 2019 (1)": 7374}, "Liabilities -- Total lease liability": {"Classification": "", "December 31, 2019": 8494, "January 1, 2019 (1)": 10322}}
lease_assets_2019 = df["Assets -- Right of use lease assets"]["December 31, 2019"]
lease_assets_2018 = df["Assets -- Right of use lease assets"]["January 1, 2019 (1)"]
answer = lease_assets_2019 - lease_assets_2018