ΛCDM consistency check. We use our amended version of CLASS to compute observables of the ΛCDM model, using the CPL parametrization with associated parameters w₀ = −1 and w_a = 0. Left-hand panels: calculation based on the parametrization which uses the early CMB-based value of H₀ = 67.56 km/sec/Mpc from Planck Collaboration VI (2020). Since this is equivalent to the standard input in CLASS for ΛCDM, we see no difference in the results. Right-hand panels: calculation based on the parametrization which uses the local value of H₀ = 73.04 km/sec/Mpc from Riess et al. (2022). The top row displays the expansion histories, while the middle and bottom rows display the CMB temperature spectra and matter power spectra, respectively. See main text for explanations.