Top panel: spectrum of the persistent emission by HE. Middle panel: detected spectrum of the bursts. Bottom panel: fraction of deficit vs. energy during the bursts detected by HE. Panel a displays the evolution of the fraction of deficit of bursts during the soft state; panels b, c, and d show the same for the hard state, and respectively display all stacked bursts, stacked bursts with insignificant hard shortage, and stacked bursts with significant hard shortage. The red solid line represents the relationship between the fraction of deficit and energy.