Light curves of PKS 1510-089. From top to bottom: variation of γ ray, V-band, 5100 Å continuum, spectral index, Hβ, Hγ, radio, and non-thermal dominance (NTD; see text) with times. The unit of γ-ray flux is photons s⁻¹ cm⁻², f₅₁₀₀ is 10⁻¹⁵ erg s⁻¹ cm⁻² Å⁻¹, emission line flux is 10⁻¹⁵ erg s⁻¹ cm⁻², and radio flux is Jy. The section between MJD = 55 000−57 100 (window A) of the spectroscopic light curves used in the time series analysis is represented by the vertical lines. The dotted line in the spectroscopic light curve is a linear fit to the data for detrending. Two horizontal lines at NTD = 1 and 2 are shown in the lower panel.