Peak continuum flux density at 1.3 mm vs. peak flux extracted in the moment 0 maps of CH₃OCHO by GExt2D. The different symbols represent the different evolutionary stages of the protoclusters: young, intermediate and evolved, as indicated on top of the figure, while the stars shows the methyl formate sources that are not associated with any compact dust continuum core. The red line shows a weighted linear fit, while the red an green shaded regions show a factor of 2 and 5 deviation from this fit, respectively.