Open Weight AI Models Lag Proprietary Capability by 4 Month Median

Open weight AI models typically trail proprietary models by a median of 4 months, according to the Artificial Analysis Progress Index v1, with the gap ranging from 2 to 8 months. The index, which tracks models released since November 2022, shows the frontier advancing by 65 to 70 points per year, with new records set roughly every four weeks. AI capabilities in China currently lag behind the U.S. by approximately 3.3 months.