Boulder County real estate sales statistics for December 2017 show a 5.45% decline in cumulative sales compared to 2016, though December sales increased by 3.5%. Inventory levels peaked in June but have since leveled out, with over 44% of active single-family home listings under contract by the end of December. A strong December indicates positive momentum entering 2018, but sufficient listings will be crucial to motivate buyers who have been waiting for more homes to appear on the market.