We asked how the number of homes delivered through legacy programmes were being tracked. Homes England told us it is using geospatial imaging to set boundaries around sites, and identify which homes can be attributed to unlocking interventions.27 The Department explained that attributing homes to financial investments is more challenging for some projects.28 It gave the example of improvements to junction 10 of the M5, where it is not straightforward to define a boundary and attribute all new homes within it to the intervention, noting that a degree of judgement is required.29