What is the total percentage of plan asset fair value allocated to cash and cash equivalents in 2018 and 2019?
{"Equity securities -- Canada": {"2019": 22.3, "2018": 20.8}, "Equity securities -- United States": {"2019": 19.8, "2018": 12.7}, "Equity securities -- International (other than United States)": {"2019": 14.1, "2018": 18.1}, "Fixed income instruments -- Canada": {"2019": 41.2, "2018": 45.7}, "Cash and cash equivalents -- Canada": {"2019": 2.6, "2018": 2.7}}
cash_and_cash_equivalents_2019 = df["Cash and cash equivalents -- Canada"]["2019"]
cash_and_cash_equivalents_2018 = df["Cash and cash equivalents -- Canada"]["2018"]
answer = cash_and_cash_equivalents_2019 + cash_and_cash_equivalents_2018