A graphical summary of Table A.1 (Instruments), A.3 (References), A.4 (Proxies), and A.5 (Composite datasets) representing almost all the datasets incorporated in SOLID versus time and wavelength. The upper panel presents all available proxies, together with two spectral composites. The lower blue line, labeled Radio, represents the 3.2, 8, 10.7, 15, and 30 cm radio fluxes from the Nobeyama and Penticton radio-observatories. The time range shown corresponds to the available times in the SOLID database, which truncates all proxies but the radio fluxes at 1969. The lower panel presents the temporal and spectral ranges for all instruments in the database. Vertical lines represent the time point and spectral range of the reference spectra. Instruments with fewer than 20 channels are shown as light boxes with a horizontal line at the wavelength of the central frequency of each channel. While the 21st century is well covered both in temporal and spectral dimensions, previous data are only available for selected wavelengths. Only the UV between 170 nm and 400 nm has been covered continuously since 8 November 1978.