The interval property of the timeline index is the time span mapped by each slot. The time span must be a date-time literal or date-time expression that evaluates to either a positive or negative duration value. The time span is evaluated at the time the load is first initialized by LoadInit, and is never altered.

If the interval evaluates as positive, the base time will represent the beginning of the timeline.

If the interval evaluates as negative, the base time will represent the end of the timeline.

Example (Positive Interval)

In the example of above, since the interval is positive, the first slot maps the 7 days following and including the base time. Hence, the first slot would map the dates from Oct 1, 2003 to Oct 7, 2003 and the second slot would map the dates from Oct 8, 2003 to Oct 14, 2003.

Example (Negative Interval)

In the example of above, since the interval is negative, the first slot maps the 7 days preceding and including the Base Time. Hence, the first slot would map the dates from Sept 25, 2003 to Oct 1, 2003 and the second slot would map the dates from Sept 18, 2003 to Sept 24, 2003.