As already noted, the unit footprint (i.e. kg CO2 per t of LPG sold) of cylinders is 2.5 times higher than that of bulk. This means that absolute-volume results can be affected by shifts in the business mix between bulk, cylinder and wholesale. These shifts cannot be controlled by SHV Energy.
To correct the change caused by increased weight of the cylinder based business, we compared the footprints on an equivalent-volume basis. In other words: what would the 2012 and 2013 footprints have been, had we used the same volume proportions in both years? On this equivalent-volume basis, the 2013 total footprint is 0.1% lower than that of 2012.