What is the value of the unbilled receivables due within 2-5 years as a percentage of the unbilled receivables due within 1 year?
{"1 year or less": {"December 31, 2019": 180219, "": 60}, "1-2 years": {"December 31, 2019": 91132, "": 30}, "2-5 years": {"December 31, 2019": 30604, "": 10}, "": {"December 31, 2019": 301955, "": 100}}
unbilled_25_years = df["2-5 years"]["December 31, 2019"]
unbilled_1_year = df["1 year or less"]["December 31, 2019"]
answer = unbilled_25_years / unbilled_1_year * 100.0