Derra Foods is a specialty food retailer. In its balance sheet, the firm reports $1 billion in book value of equity and no debt, but it has operating leases on all its stores. In the most recent year, the firm made $85 million in operating lease payments and its commitments to make lease payments for the next 5 years and beyond are summarized.

YearOperating Lease Expense

1 $ 90 million

2 $ 90 million

3 $ 85 million

4 $ 80 million

5 $ 80 million

6-10 $ 75 million

annually If the firm's current cost of borrowing is 7%, estimate the debt value of operating leases