We calculate durations and spectral parameters for 218 Swift bursts detected by the BAT instrument between and including GRBs 041220 and 070509, including 77 events with measured redshifts. Incorporating prior knowledge into the spectral fits, we are able to measure the characteristic νFν spectral peak energy Epk,obs and the isotropic equivalent energy Eiso (1–10 4 keV) for all events. This com...