Select the multiline text object you want to edit.
In the Properties palette, for Line Space Style, select one of the following:
At Least. Adjusts lines of text automatically based on the height of the largest character in the line. More space is added between lines of text with taller characters. This is the default setting.
Exactly. Forces the line spacing to be the same size for all lines of text regardless of format differences such as font or text height.
Change the line spacing by entering a new value for either of the following options. The two line spacing options provide different ways to set the same thing:
Line Space Factor. Sets the line spacing to a multiple of single-line spacing. Single spacing is 1.66 times the height of the text characters.
Line Space Distance. Sets the line spacing to an absolute value measured in drawing units. Valid values must be between 0.0833 and 1.3333.
Note: After you exit the Properties palette, the value of the other line spacing option is updated to correspond with the line spacing value that you entered.