The assessment is based on the high authority and relevance of the primary sources provided, which are the definitive sources for tracking capital flows in the US. The Investment Company Institute (ICI) directly measures and reports on inflows and outflows for mutual funds and ETFs, which represent a major component of capital movements into the equity markets. The Federal Reserve Economic Data (FRED), which hosts the comprehensive 'Financial Accounts of the United States', provides a broader, corroborating view of capital flows from all sectors.The economic context since the beginning of 2020, marked by significant fiscal and monetary stimulus, led to a widely documented and unprecedented surge in investment into equity markets, particularly in 2021. Numerous financial reports citing ICI data have noted that inflows during this period surpassed the combined totals of many previous years, which strongly supports the "record" aspect of the claim. While the exact figure of $1.6 trillion depends on the precise end-date and methodology (e.g., whether it includes only funds or all net equity purchases), the order of magnitude is highly plausible given that inflows in 2021 alone approached $1 trillion. The primary sources provided are exactly the ones required to verify such a statement, and there is no conflicting evidence among them. The other sources are either secondary commentary that would likely rely on this primary data or irrelevant as they measure market performance rather than capital flows.