ESDU Struct 02.01.48 gives graphs from which the buckling stress coefficient of a plate symmetrically tapered in plan may be obtained for all four cases of a pair of opposite edges either clamped or simply-supported. Uniform compressive loads that need not be equal are applied to the parallel sides. For each edge condition three loadings are treated with the ratio of the stress in the narrower edge to that in the wider edge having values of 0.8, 1 and 1.2; it is assumed that any imbalance in the loads is balanced by shear applied to the non-parallel edges. The resulting 12 graphs give curves of buckling stress coefficient plotted against the ratio of the length of the plate to its greater width for fixed values of the ratio the widths of the parallel sides. For the case of equal stresses in the parallel edges, an additional set of curves applies to the case when there is constant longitudinal stress and no displacement normal to the axis of taper. The buckling stress coefficient is defined as the stress at buckling non-dimensionalised by the modulus of elasticity of the material and factored by the square of the ratio of the greater width of the plate to its thickness. The data apply to materials that are isotropic and have Poisson's ratio of 0.3.