Abstract: This paper provides the first internationally comparable estimate of the size and budgetary cyclical sensitivity of automatic fiscal stabilizers in Vietnam, applying the budget semi-elasticity framework of the OECD and the European Commission to a single revenue classification, the OECD Revenue Statistics for Viet Nam, over 2003 to 2024. The framework is given an explicit analytical foundation: the semi-elasticity is derived from the budget identity, and three propositions establish an upper bound that depends only on revenue shares, the effect of labor informality, and the propagation of estimation error. The revenue-side semi-elasticity is estimated at +0.007, with a bootstrap confidence interval of [−0.052, +0.067], and lies within one hundredth of zero in all three sample windows examined; Proposition 1 bounds it below 0.113 under the most generous treatment of the point estimates. The cyclical response of unemployment insurance expenditure cannot be distinguished from zero, in a test with the power to detect a coefficient of 0.11. Combining the two sides with the measured size of general government gives a semi-elasticity of the budget balance of 0.255, with a ninety-five percent interval of [0.194, 0.315], roughly half the European Union average of 0.50. A panel of seven Asia-Pacific economies yields a closely similar estimate of 0.246 (standard error 0.097) once the discretionary stimulus episodes of 2009 and 2020 to 2021 are separated; without that separation, the coefficient doubles. A decomposition against published European figures attributes 87.7 percent of the gap to the size of general government and 39.6 percent to the design of unemployment insurance, with the revenue side working in the opposite direction. What distinguishes Vietnam is therefore not the cyclical behavior of its tax system but the scale of its budget and the reach of its unemployment insurance.

Keywords: automatic fiscal stabilizers, budget semi-elasticity, budgetary cyclical sensitivity, government size, tax buoyancy, fiscal policy, Vietnam, ASEAN

Pages: 2148-2164