The difference, denoted in basis points, between the market cap rate and the yield-on-cost . The Development Spread measures the “development pop”, or value-added by taking on the construction and lease-up risk. The greater the development spread, the more likely a development project will be deemed financially feasible.
Think of it in these terms. A real estate investor has the option to either a) acquire a fully-built and stabilized asset at some market cap rate or b) construct and lease-up a brand new property at some yield-on-cost. In order to make the latter worthwhile, a benefit commensurate with the risk must be gained, otherwise there is no incentive to take on the development risk. One way the developer and its capital partners measure the potential benefit is by looking at the difference in yield between the two options, or the Development Spread.