A field's width value is specified as a percentage of the total box width. In organizing the fields within the activity box, The Activity Network will attempt to fit as many fields as possible in the first row of the activity box until the combined width of fields are equal to or exceed 100(%). Then it will attempt to fit the remaining fields on the second row of the activity box, continuing on in this fashion until all of the fields listed in the table are displayed in the activity box. Therefore, to display a field on a separate row, increase its width value such that it will no longer fit on its current row with the previous field.
For example, if you want to fit three fields in the same row, you can specify field widths of 33%, 33%, and 34%. If you want to fit the first field on its own row and the second and third fields on a single row, you can specify field widths of 68%, 33%, and 34%.