Using a new narrative measure of fiscal policy shocks for the U.K., we show that households with mortgage debt exhibit large and significant consumption responses to tax changes. Homeowners without a mortgage, in contrast, do not adjust their expenditure, with responses not statistically different from zero at all horizons. We compare our findings to the predictions of traditional and newer theories of liquidity constraints, providing a novel interpretation for the aggregate effects of tax changes on the macroeconomy.

Using a novel source of quasi-experimental variation in interest rates, we develop a new approach to estimating the Elasticity of Intertemporal Substitution (EIS). In the U.K., the mortgage interest rate features discrete jumps—notches—at thresholds for the loan-to-value (LTV) ratio. These notches generate large bunching below the critical LTV thresholds and missing mass above them. We develop a dynamic model that links these empirical moments to the underlying structural EIS. The average EIS is small, around 0.1, and quite homogeneous in the population. This finding is robust to structural assumptions and can allow for uncertainty, a wide range of risk preferences, portfolio reallocation, liquidity constraints, present bias, and optimization frictions. Our findings have implications for the numerous calibration studies that rely on larger values of the EIS.