What is the change in valuation allowance in 2019?
{"Year Ended December 31 -- ": {"2019": 2019, "2018": 2018}, "Year Ended December 31 -- Vaulation allowances, beginning of year": {"2019": 5398, "2018": 13872}, "Year Ended December 31 -- Net operating loss": {"2019": 3284, "2018": 1920}, "Year Ended December 31 -- Expiration of net operating losses and limitations": {"2019": -7, "2018": -9939}, "Year Ended December 31 -- Adjustment to deferred taxes": {"2019": 29, "2018": -321}, "Year Ended December 31 -- Impact of state tax rate change": {"2019": 26, "2018": -146}, "Year Ended December 31 -- Other adjusments": {"2019": 9, "2018": 12}, "Year Ended December 31 -- Valuation allowance, end of year": {"2019": 8739, "2018": 5398}}
valuation_2019 = df["Year Ended December 31 -- Valuation allowance, end of year"]["2019"]
valuation_2018 = df["Year Ended December 31 -- Vaulation allowances, beginning of year"]["2019"]
answer = valuation_2019 - valuation_2018