Values of n_e extracted from the DM time series shown in Fig. 11. The black points represent the epochs that have |solar_angle|< 45°. The blue points are obtained from the results presented in Tiburzi et al. (2021). The order of the pulsars is aligned according to their distance from the Sun in terms ecliptic latitude in ascending order. The long term solar cycle is evident in pulsars more than 3° away from the Sun in terms of ecliptic latitude i.e. the bottom four panels.