Comparison of the integrated S/N distribution for a selection of HI surveys as indicated in the legend. The left panel shows the normalised count, while the right panel shows the cumulative distribution. The horizontal range has been truncated to values <30 in order to show the shapes of the distribution more clearly. It should be noted that these S/N_int values, while calculated using the original survey data, do not present a fair comparison for assessing source extraction methods (see Fig. 11 for a more accurate comparison).