2.4.4.342 SpLine
The SpLine cell is a vLength custom token grouping that specifies the height of a line of text in the text block of a shape. It MUST have a Row_Type parent element that has a Paragraph Section_Type parent element.
If the value of the structure is greater than or equal to zero, then the height of the line is equal to the value of the structure. If the value of the structure is less than zero, then the height of the line is equal to the absolute value of the structure multiplied by the largest font size of text in the line.