The range of attribute levels (that is, percentage deviations from the base levels) to appear across the choice alternatives was selected to be representative of the potential variation in outcomes that could be observed under carbon pricing and the addition of short sea shipping services over time. These impacts and ranges were hypothesised to be different across modes (for example, prices for road freight services should experience higher variability due to a relatively larger burden through carbon taxes), resulting in the following ranges of attribute levels across alternatives, as shown in Table 1.