Variation of TiO 7050 index as a function of stellar spectral type for the CARMENES GTO sample with N_obs > 25. The CRX-slope sample of stars is indicated by diamonds which are filled for Hα active stars and open for Hα inactive stars. The CRX-slope sample stars are coloured depending on CRX-gradient (left panel) and CRX-length (right panel). The stars are labelled as indicated in Table A.1.