Factor #1:

Congressional Budget Office, “Budget and Economic Data,” under the headings “Historical Budget Data/ Revenues, Outlays, Deficits, Surpluses, and Debt Held by the Public Since 1967” and “10-Year Budget Projections/CBO’s Baseline Budget Projections, by Category,” June 2017, here. There is no formula for this factor because CBO provides the figures directly.

Factor #2:

Office of Management and Budget, “Historical Tables,” Table 7.1, May 2017, here Congressional Budget Office, “Budget and Economic Data,” under the headings “10-Year Budget Projections/Federal Debt Projected in CBOs Baseline,” Table 5, June 2017, here; Congressional Budget Office, “Budget and Economic Data,” under the headings “10-Year Economic Projections/June 2017 Baseline Projection – Data Release (Fiscal Year),” here. This data is used in the following formula: gross federal debt ÷ gross domestic product = % of gross domestic product.

Factor #3:

Department of the Treasury, “Interest Expense on the Debt Outstanding,” here (accessed January 18, 2018); Congressional Budget Office, “Budget and Economic Data,” under the headings “Historical Budget Data/“Historical Budget Data/ Revenues, Outlays, Deficits, Surpluses, and Debt Held by the Public Since 1967” June 2017, here; Congressional Budget Office, “Budget and Economic Data,” under the headings “10-Year Budget Projections/CBO’s Baseline Budget Projections by Category” and “Spending Projections by Budget Account (specifically Line 1682, “Interest on Treasury Debt Securities (gross)”), January 2017, also here. This data is used in the following formula: gross federal interest costs ÷ federal revenues = % of federal revenues.

Factor #4:

Office of Management and Budget, “Historical Tables,” Table 7.1, May 2017, at here; Congressional Budget Office, “Budget and Economic Data,” under the headings “10-Year Budget Projections/Federal Debt Projected in CBOs Baseline,” Table 5, June 2017, here; Department of the Treasury, “Interest Expense on the Debt Outstanding,” here (accessed January 18, 2018); Congressional Budget Office, “Budget and Economic Data,” under the headings “10-Year Budget Projections/CBO’s Baseline Budget Projections by Category” and “Spending Projections by Budget Account (specifically Line 1682, “Interest on Treasury Debt Securities (gross)”), January 2017, also here. The data is used in the following formula: gross interest costs in year z ÷ gross debt at the end of year z – gross debt at the end of year y = percent of new debt. Please note that after reviewing the data in more depth, I re-set the threshold at 70 percent as opposed to 80 percent.

Factor #5:

Office of Management and Budget, “Historical Tables,” Table 7.1, May 2017, here; Congressional Budget Office, “Budget and Economic Data,” under the headings “Historical Budget Data/ Revenues, Outlays, Deficits, Surpluses, and Debt Held by the Public Since 1967” and “10-Year Budget Projections/CBO’s Baseline Budget Projections, by Category,” June 2017, here. The data is used in the following formula: debt held by the public ÷ gross debt = percent of gross debt.

Factor #6:

Here; here. The historic data is used in the following formula: debt held by the Federal Reserve ÷ debt held by the public = percentage of debt held by the public. The formula for the projected data is the same, but the data assumes the Federal Reserve will draw down its share of the debt held by the public by simply maintaining the dollar value of its debt at current levels. This approach permits the Federal Reserve to return its holdings as a share of the debt held by the public to about the levels of 2008 on a gradual basis.

Factor #7:

here, under the heading “Ownership of Federal Securities;” here; here. The historic data is used in the following formula: the dollar value of the foreign-held debt ÷ the debt held by the public = percentage of debt held by the public. The formula for the projected data under this factor is: the dollar-level of foreign-held debt based on the average annual rate of increase in these holdings from the historic data ÷ the projected debt held by the public = the percentage of debt held by the public.

Factor #8:

Here; here. The historic data is used in the following formula: the dollar value of TIPS outstanding ÷ debt held by the public = the percentage of debt held by the public. The projected data is used in the following formula: the dollar value of the TIPS outstanding based on a 15 percent annual rate of increase ÷ by the projected debt held by the public = percentage of debt held by the public.

Factor #9:

Here; here; There is no formula for the historic data under this factor because OMB provides the amounts directly. The projected data is used in the following formula: the dollar-level revenues projected in the June 2017 CBO baseline – the loss of revenues projected by CBO in its assessment of H.R. 1 ÷ projected GDP = percentage of GDP.