Total solar irradiance over cycle 23: reconstructed using SATIRE-S from 60-min averaged MDI magnetograms (red diamonds; consecutive days are connected by red lines) and measured. Measurements by two instruments, ACRIM II (pine green) and TIM/SORCE (light green), are shown as well as the PMOD composite of measurements (blue). In the bottom panel, measurements are only shown on the days when the SATIRE-S values based on 60-min MDI magnetograms are available.