Start with the number, because the number moved fast.

Google has agreed to cover as much as $44bn of lease payments on data centres owned by other people, should the tenant default. It disclosed the figure last week. At the end of September the same commitment stood at $6.5bn, The Information reported.

That is close to seven times larger in nine months.

The promise is simple to state and hard to price. Google does not own the building. It does not occupy the building. It has told the lenders that if the company renting the building stops paying, Google will.

Why a search company is underwriting other people’s rent