Gets or sets a value to be added to or subtracted from the Value property when the scroll box is moved a large distance.
published property LargeChange: Integer read GetLargeChange write SetLargeChange default 5;
When the user presses the PAGE UP or PAGE DOWN key or clicks the track bar on either side of the scroll box, the Value property changes according to the value set in the LargeChange property. You might consider setting the LargeChange value to a percentage of the Height (for a vertically oriented track bar) or Width (for a horizontally oriented track bar) value. This keeps the distance your track bar moves proportionate to its size.