Tomorrow morning's existing-home sales report for June from the NAR (National Association of Realtors) is widely expected to receive a boost from the expiration of the federal home purchase tax credit at the end of that month. However, analysis of pending home sales data (also from the NAR) leads to a projection for a low number of existing home sales for June.The NAR describes the value of pending home sales data as follows: Specifically, Pending Home Sales become Existing-Home Sales one-to-two months later. This means that we can use an index derived from Pending Home Sales to predict actual home sales activity. Since pending home sales measure actual existing-home sales, the PHSI provides an accurate and reliable indicator of future home sales activity. Our sample shows that over 80% of all pending home sales go to settlement within a 2-month time-period (and a significant share of the rest close in month 3 and month 4). Because of the expiration of the home purchase tax credit, some closings may have been accelerated into June. That occurrence could introduce a bias into the historical correlations. Even so, the projections from those correlations are sufficiently low that such bias could still leave existing home sales below what many are expecting.