Select scale > Editor > Edit Scale > Time
Use to edit the time scale for the x-axis.
Time Scale
Index: Choose to label the x-axis with integers.
Calendar: Choose to label the x-axis with a calendar scale, then choose the calendar units.
Clock: Choose to label the x-axis with a clock scale, then choose the clock units.
Stamp: Choose to label the x-axis with values from one or more stamp columns.
Stamp columns (1-3): Enter up to three columns containing scale values.
Start Values
One set for all variables: Choose to use the same start values for each variable. Type the start value for each component of the time scale.
One set for each variable: Choose to use a different set of start values for each variable, if there are overlaid variables. For each variable, type the start values for each component of the time scale you chose.
Data Increment: Uncheck to enter the data interval between values on the innermost time scale.