Fiscal policy in the US: a new measure of uncertainty and its effects on the American economy

We use the dispersion of the Federal Budget Balance forecasts from Consensus Economics to construct a new measure of fiscal uncertainty; constant horizon forecasts are obtained through mixture distributions. The scheme we propose has several advantages over previous uncertainty measures. First (as opposed to recent proposals), it results in a forward-looking measure, which implies that any sudden development in terms of an (un)expected fiscal stance is immediately incorporated in the series. Second, the measure is by construction a real-time one. Third, being completely model-free, it is not contaminated (inflated) by model uncertainty. Fourth, our measure does not simply track uncertainty stemming from public consumption and investment, whereas it is comprehensive in also accounting both for the critical welfare component of public expenditure and for taxes. Fifth, as opposed to uncertainty indexes which can be interpreted only dynamically, our measure has an obvious intuitive point-wise interpretation. Interestingly, the inception of the Trump administration has led to unprecedented uncertainty shocks which have demonstrably put a non-negligible brake on the slow US recovery. More generally, we show that fiscal uncertainty shocks have clear recessionary effects. Furthermore, constraints on monetary policies during the ZLB have likely strengthened the recessionary effects of fiscal uncertainty shocks.