US Forecast: January 28, 2018
Forecast Period

2018:1--2025:4 (32 quarters)


The forecast is based on the national income and product accounts (NIPA) data that were released on January 26, 2018.

The Latest Version of the US Model

For purposes of this forecast the US model has been reestimated through 2017:4. These estimates and the complete specification of the model are presented in Appendix A: The US Model: January 28, 2018. A complete discussion of this version of the US model is in Macroeconometric Modeling: 2018.

Unless otherwise noted, the flow variables in the model are presented in this memo and on the site at quarterly rates. This is a change from versions dated July 31, 2011, and back, where the flow variables were presented at annual rates. To convert quarterly rates to annual rates, just multiply by four.

Assumptions Behind the Forecast

The table below gives the growth rates that were assumed for the key exogenous variables in the model along with the actual growth rates between 2010:1 and 2017:4.

                 Growth Rates (annual rates)

           Forecast                         Actual     
          Assumptions                   2010:1-2017:4  

TRGHQ         2.0                           -0.1       
COG           1.0                           -1.5       
JG            1.0                           -0.0       
TRGSQ         2.0                            8.2       
TRSHQ         2.0                            0.2       
COS           1.0                           -1.2
JS            1.0                           -0.0       
EX            3.0                            3.6
PIM           1.0                            0.0

The first seven variables are the main government policy variables in the model aside from tax rates. TRGHQ is real federal government transfer payments to households, COG is real federal government purchases of goods, JG is federal government civilian employment, TRGSQ is real federal government transfer payments to state and local governments, TRSHQ is real state and local government transfer payments to households, COS is real state and local government purchases of goods, JS is state and local government employment, EX is real exports, and PIM is the import price deflator.

All tax rates were taken to remain unchanged from their 2017:4 values except for the personal income tax rate, D1G, and the corporate profit tax rate, D2G, which are affected by the tax bill that was passed at the end of 2017. Estimates from the Joint Committee on Taxation, December 18, 2017, were used to guide the choice of values for D1G and D2G. Also, TRFG, which is the value of transfers from firms to the federal government, was changed to reflect the Committee's estimates of the revenue gained from the repatriation of profits from abroad. So three variables were changed to reflect the tax-law changes.

The above assumptions regarding the state and local government variables result in roughly balanced budgets over time in the forecast.

No assumption is needed about monetary policy for the forecast because monetary policy is endogenous. Monetary policy is determined by equation 30, an estimated interest rate reaction function or rule.

The Forecast

Forecasts of selected variables are presented in the following: Forecasts of selected variables---html, Forecasts of selected variables---pdf file. If you want more detail, click "Solve current version" after "US Model," create a data set, and then go immediately to "Examine the results without solving the model." You can then examine any variable in the model.

Real GDP Growth and the Unemployment Rate: The forecast has real GDP growing at 4.0, 3.3, 2.9, and 2.7 percent in the next four quarters, respectively. It is then predicted to grow betwen about 2 and 2.5 percent for the rest of the horizon. (All growth rates in this memo are at annual rates.) The unemployment rate is between about 4 and 4.5 percent throughout the forecast period.

Inflation: Inflation as measured by the growth of the GDP deflator (GDPD) is between 2.1 and 2.5 percent throughout the forecast period.

Monetary Policy: The estimated interest rate rule (equation 30) is predicting that the three month bill rate (RS) will gradually rise to 4 percent by 2020. It is 5.2 percent at the end of 2025.

Federal Government Budget: The federal government budget deficit as a percent of GDP, variable SGPZGDP, rises to 5.0 percent by the end of 2025. The debt/GDP ratio, variable AGZGDP, is 89.0 at the end of 2025, up from 69.1 in 2017:4. It was 46.1 percent in 2007:1. The federal government debt, variable -AG, is $25.3 trillion at the end of 2025. hich is 82.9 percent of nominal GDP (variable AGZGDP in the model). Interest payments of the federal government as a percent of GDP, variable INTGZGDP, rises to 5.1 percent at the end of 2025. At the end of 2025 federal government interest payments are roughly equal to federal government budget deficit.

U.S. Current Account: The deficit in the U.S. current account, variable -SR, is roughly constant throughout the period.

Comments on the Forecast and Possible Experiments to Run

The main message from the current forecast is that if there are no bad shocks the economy is roughly at full employment throughout the forecast period.

The assumption of no bad shocks, which is used for the forecast, means that stock prices, housing prices, and import prices grow at historically normal rates. There are no negative wealth shocks through falling stock prices and housing prices. Changes in asset prices like stock prices, housing prices, exchange rates, and oil prices are essentially unpredictable. One can use the US model to analyize the effects of asset price shocks, but the shocks themselves cannot be predicted. The best one can do in a forecast is to assume some historically average behavior of asset prices, which has been done here.

To examine the effects of asset price shocks, experiments can be run using the model in which stock prices (variable CG), housing prices (variable PSI14), and import prices (variable PIM) are changed. This allows one to examine the sensitivity of the forecast to changes in these values.

To review, oil price shocks and exchange rate shocks are handled through changes in PIM. Housing price changes are handled through changes in PSI14. Changes in PSI14 change PKH relative to PD and thus change housing wealth, PIH*KH. This affects consumption expenditures through the total wealth variable AA (equations 1, 2, and 3). It affects housing investment through the housing wealth variable AA2 (equation 4). Regarding the stock market, each change in the S&\P 500 index of 10 points is a change in CG, the capital gains variable in the model, of about $100 billion. If you think that the S&\P index will fall, say, 100 points, you should drop the equation for CG and change CG by about -$1,000 billion. See the discussion in Section 7.2 of The US Model Workbook, January 28, 2018. This will have a negative effect on real output growth because of a negative wealth effect.