What is the change in capital losses from the UK between 2018 and 2019?
{"Revenue losses  UK": {"2019": 398.4, "2018": 300.8}, "Capital losses  UK": {"2019": 34.5, "2018": 34.2}, "Derivative financial instruments": {"2019": 172.7, "2018": 184.9}, "Other temporary differences": {"2019": 20.1, "2018": 9.7}, "Total unrecognised temporary differences": {"2019": 625.7, "2018": 529.6}}
capital_losses_uk_2019 = df["Capital losses  UK"]["2019"]
capital_losses_uk_2018 = df["Capital losses  UK"]["2018"]
answer = capital_losses_uk_2019 - capital_losses_uk_2018