What was the change in the Restricted cash between 2018 and 2019?
{"Cash": {"2019": 85688, "2018": 99197}, "Money market funds and other": {"2019": 138073, "2018": 198072}, "Restricted cash": {"2019": 2493, "2018": 417}, "Total cash and cash equivalents and restricted cash": {"2019": 226254, "2018": 297686}}
restricted_cash_2019 = df["Restricted cash"]["2019"]
restricted_cash_2018 = df["Restricted cash"]["2018"]
answer = restricted_cash_2019 - restricted_cash_2018