When you select the drafting standard, the default settings for taper and slope symbols change to match that drafting standard.
You can customize these settings to suit your drafting requirements
Because text and leader lines are the most common objects used for annotations, AutoCAD Mechanical toolset provides a single configuration point (the Standard Settings dialog box) enabling you to specify their default properties. These settings are the master settings.
In the Taper and Slope Settings dialog box, the text and leader settings default to “By NameOfCurrentDraftingStandard.” If you modify the master settings, taper and slope symbols automatically acquire the new settings. If you do not want the taper and slope symbols to follow the master settings, override the text height and select a specific value.
You can also specify whether the slope/taper rate is expressed as a ratio or as a percentage, by default. If you select ratio, you can specify how to represent the ratio.