Sky-rocketing home prices surprised just about everyone in the first half of 2021. Last week’s S&P Case Shiller index provides the most recent evidence, with the national index rising 14.6% year over year in April. The index measures comparable sales over the trailing three months to adjust for differences in the quality of homes sold in each period. The April reading marked a record high in the level of the index and a 30-year high in month-over-month growth.