Since 1946, the assets of U.S. financial intermediaries, even excluding the outsized growth in mortgage pools, have risen 1.8 percent per year relative to nominal GDP. From 1896, the earliest date of comprehensive data on bank assets, to 1941, assets of banks, by far the predominant financial intermediaries in those years, rose 0.6 percent per year relative to GDP.
The increase in the ratio of deficits of individual economic entities to GDP, as I noted earlier, is reflected in an ever-rising ratio of unconsolidated levels of debt to GDP. Facilitating the ability of residents of the United States and, presumably, other economies to accumulate this debt with limited stress has been the rising ratio of the market value of nonfinancial assets to GDP.