Single-family houses on their own, from permit through start and completion to the sale itself. Keeping them apart from the all-structure pipeline is what makes the distances on this chart mean something: every line counts the same kind of house, so the gap between what was finished and what sold is a real gap rather than the apartment stock. Read the four as four views of one market and not as a funnel. A house counts as sold when the contract is signed, at whatever stage it has reached, so some of each month’s sales are houses nobody has broken ground on. The months’ supply below the chart is the balance: how long the unsold stock would last at the pace houses are selling now.
Census and HUD via FRED · single-family building permits, starts, completions and new home sales, with the months’ supply, monthly