The United States Statistical Release Z.1 now has a new look and more data. It now includes the Integrated Macroeconomic Accounts.
According to the Intergated Macroeconomic Accounts site (which was available separately but online only):
These tables present a sequence of accounts that relate production, income and spending, capital formation, financial transactions, and asset revaluations to changes in net worth between balance sheets for the major sectors of the U.S. economy. They are part of an interagency effort to further harmonize the BEA National Income and Product Accounts (NIPAs) and the Federal Reserve Board Flow of Funds Accounts (FFAs).
The structure of these tables is based on the internationally accepted set of guidelines for the compilation of national accounts that are offered in the System of National Accounts 1993 (SNA).
So now you can look at things such as households’ capital gains easily from the Z.1. Such as from the table below: