# Time Scale & Range

The Time Scale & Range panel in the timeline properties pane is used to adjust the range of time the timeline reflects and the scale in which it is measured. The controls that are displayed depend on the "Timeline Type" that is selected. For more information about the differences between the two timeline types, see "Calendrical vs. Sequential Timelines".

## Timeline Type

The "Timeline Type" control allows you to specify whether you want your timeline to be date-based (Calendrical) or a simple ordinal series of events (Sequential).

## Calendrical Timeline Controls

In Calendrical mode, the timeline requires a reference date on which the timeline starts, the span of time it covers, and a scale in which the intervals are measured (such as years, months, etc.).

### Time Scale

The time scale determines how much time passes between each minor interval (or small 'tick-mark' on the timeline). For example, if the scale is set to "Years", each minor interval represents one year. The scale can be expressed in years, months, days, hours, minutes, or seconds.

### Reference Date

The reference date determines the starting interval of the timeline, expressed in year, month, day, and time (hour, minute, and second). Although you can specify each of these, you only need to specify the components you want to display or keep track of. For example, if you set the scale to "days", you might only care about the month and day (such as "October 31 - November 15th". All others can be ignored.

### Span

The span affects the length of time your timeline covers, starting from the reference date. For example, if you've set the scale to years, set the reference date 1900 and set the span to 100, your timeline will span 100 years, ending in 2000. Similarly, if you've set the scale to months, set the reference date to March, 1999 and set the span to 24, your timeline will span 2 years (24 months), ending in March, 2001.

## Sequential Timeline Controls

In Sequential mode, the timeline requires only a start interval and a span.

### Start Interval

The start interval is used as the beginning of the timeline (the first interval) and can be expressed as any number, positive or negative. For a sequential list of actions, for example, you might want to set the start interval to 1.

### Span

The span affects the length of your timeline. If the start interval is 0 and the span is 100, for example, your timeline will end at 100. For a list of 1-10, you can set the start interval to 1 and the span to 9, totaling 10 intervals.

# Notes

Changing the timeline type, the start interval, the reference date, or the span after you've added events may affect the events' start intervals and spans.

Although the scale you choose in a Calendrical timeline affects the value of a single interval, you can still display the date any way you wish. For example, you can start a timeline in December of 1999 and span 12 months with the scale set to Months. If you set the date format to display the month and year, the timeline will be titleed like this: "December 1999, January 2000, February 2000, .....". You can adjust the date formatting using the "Date & Title Appearance" adjustment panel.

If you make a mistake, you can always undo!