Top panel: bar semi-major axis vs. corotation radius for the high- and low-redshift sample. The sample was divided into three redshift bins; z ≈ 0 (solid black circles), z < 0.5 (solid blue squares), and z > 0.5 (solid red stars). The solid, dotted and dashed lines represent the values, from linear theory, of ℛ = R_CR/R_bar = 1.0,1.2 and 1.4, respectively. This range corresponds to what is considered in the literature as fast bars (see Sect. 1). Bottom panel: outer ring radius vs. bar semi-major axes radius for the high- and low-redshift sample, the symbols and lines are the same as those represented in the top panel. Notice that all galaxies, regardless of their redshift, clearly fall into the “fast-bar” region.