Appearance Settings - Scale
The Scale settings control the units your timeline's axis uses and the span of time it covers.
To reach these settings, click the Appearance button above your timeline and open the Scale section. You can preview one or more changes before applying them: click Save Changes to apply them and close the dialog, or Cancel to close it without saving.
Units
By default, Preceden picks the scale that best fits your timeline's date range. To set it yourself (for example, when Preceden picks weeks and you want months), choose the units here.
The dropdown opens on Automatically optimize and then lists every unit from the smallest to the largest: Seconds, Minutes, Hours, 2 Hours, 4 Hours, Days, Weeks, 2 Weeks, Months, Quarters, Years, 2 Years, 5 Years, Decades, Quarter Centuries, Half Centuries, Centuries, Millennia, 10 Millennia and 50 Millennia. That range is why the same editor works for a conference schedule measured in hours and for a timeline covering tens of thousands of years.
Not every scale works with every timeline. A timeline spanning years can't be shown in days, for example, because that would take hundreds of axes. When that happens, Preceden shows a notice on your timeline with a Have Preceden determine the best scale link that puts the units back on Automatically optimize. Learn more about resolving scale issues.
If the axes run far past your last event, with the dates across the top stretching decades beyond where your events end, a few events probably have long names: Preceden widens the date range so each name displays in full. Shortening those names pulls the axes back in.
Date Range
This setting controls the span of time your timeline covers. Display all events, the default, adjusts the dates so that every event is visible. Zoom into date range lets you enter a specific start and end date, and Range relative to today shows a window of time before and after today's date. Learn more about zooming.
Range relative to today counts in the units you chose above, from 1 to 15 on each side of today (for example, 2 months before and 4 months after), so it only works when Units is set to something other than Automatically optimize. If you leave the units on automatic, saving returns an error asking you to pick one.