Plots > Working with Plots > Axes and Tick Marks > To Customize Tick Marks
  
To Customize Tick Marks
1. Select a plot to customize.
2. To toggle the display of tick marks or tick mark values, on the Plots tab, in the Axes group, click one of the following options:
Tick Marks
Tick Mark Values
3. To toggle the tick marks scaling, on the Plots tab, in the Axes group, click Logarithmic Scaling. Both the axis and the tick marks toggle between linear and logarithmic scaling.
4. To format the tick mark values of an axis, click an editable tick mark on that axis, and on the Plots tab, in the Format Plot Values group, select the desired formatting options. Both the axis and the tick marks are affected.
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If you change the tick marks format, marker callouts format are changed.