Number counts at 250 μm (top panel), 350 μm (middle panel), and 500 μm (bottom panel). The contribution of z < 0.5, z < 1, z < 2, and all sources are plotted in violet, blue, green and red, respectively. Squares: points from stacking in GOODS-N. Triangles: points from stacking in COSMOS. Diamonds: points measured from source extraction using priors. Vertical dotted line: 4-σ confusion limit. Long and short dashed lines: extrapolation of the counts and 1-σ confidence region (see Sect. 9.2.1). Plus symbols: Béthermin et al. (2010b) measurements using BLAST data. Circles: Oliver et al. (2010b) measurements from resolved sources in the HerMES science demonstration phase data (Herschel/SPIRE). Crosses: Clements et al. (2010) measurements from resolved sources in the SPIRE H-ATLAS science demonstration phase data (Herschel/SPIRE). Asterisks: Glenn et al. (2010) measurements from P(D) analysis of the HerMES science demonstration phase data (Herschel/SPIRE).