Dusting off my actuarial skills:
UPS earned $9.972 million in interest from the time the contract was ratified to July 1st
assuming:
- The $660 million was "owed" evenly in lump pmts from the end of Aug to the end of April,
- Interest was compounded monthly, and
- UPS was able to "earn" 3% annually on the funds during through June 30th.
At 6% annual return, the amount is $20.102 M.