US home sales just ended a 39-month year-over-year decline, signaling the end of the bear market, NDR said.Affordability issues, driven by high mortgage rates, drove the 3-year decline in home sales activity.Investors could take advantage of the setup by buying the iShares U.S. Home Construction ETF, NDR said.The bear market in US home sales is finally over, according to a recent note from Ned Davis Research.The firm highlighted that total single-family home sales finally turned positive year-over-year after 39 months of consecutive declines.The 39-month decline in home sales was only outdone by the 43-month decline during the housing bubble from 2005 through 2009."But the recent affordability-driven pandemic bear could not be more different than the credit-driven housing bubble bear," Pat Tschosik, a strategist at Ned Davis Research, said.The main difference between the two notable declines in home sales is affordability.Whereas the affordability index rose 53 points from 2005 through 2009, it plunged 39 points from 2021 through 2024, driven by high mortgage rates and ever-rising home prices. Ned Davis Research "Homeowners, locked into low rates and unwilling to move, added to low supply and higher prices," Tschosik said.Additionally, the stocks of homebuilders outperformed over the past three years, compared to them underperforming during the 2005 through 2009 stretch.The recent rebound in home sales activity suggests to Tschosik that the housing market should thaw in 2025, enabling a rebound in durable and home improvement spending.For investors, that means the iShares U.S. Home Construction ETF could be a worthy addition to portfolios for next year. The ticker symbol is "ITB.""We are watching ITB for an upgrade. If inflation fears are overblown, the recent ITB correction could be a great buying opportunity," Tschosik said.The ETF has declined by more than 15% since fears of a rebound in inflation gripped the market in late November.The top holdings within the Home Construction ETF include home builders D.R. Horton, Lennar Corp, NVR, and Pulte Group, as well as home-improvement retailers Home Depot and Lowe's.