From top to bottom panel: column densities of the cold and the warm obscurer, covering fraction of the cold and the warm obscurer plotted as function of the flux in the UVW2 filter. Column densities are plotted in units of 10²² cm^-2. The UVW2 flux is plotted in units of 10^-14 erg s^-1 cm^-2 A^-1. Black diamonds and red asterisks identify parameters measured with XMM-Newton and Chandra-LETGS, respectively. Error bars, when larger than the size of the plotting symbol, are also shown. Upper limits are plotted as an arrow. Crosses represent values that were kept frozen in the fits.