Period Data
It is displayed to grasp an age background in one chronological table.
It consists of the ones with name and end date, start date, and so on.
The Period Data belonged to on one chronological table are displayed in Period Data view
When [ Select ] button is pressed, "Period Selection List" window appears.
Checked items are belonged to its table.
If checked item were changed, belonged period data are changed.
When you want to add new period data, please push 
button.
When you want to change a period data,
please select item and push 
button.
Add Period Data
"Period Data Registration" window is generated by ![[ + ]](../gfx/addbttn.png)
button of "Period Selection List" window.
Text Color,Background Color can be selected from left "Text Color / Background List". It's list can be added/edited by above buttons.
When "Add Tag" checkbox is checked and [Set Color >>] is pressed, The name of list item is added to Tag of right part.
It can be registered only Period Name and Start Date.
Change Period Data
When one period item is selected and pressed ![[ * ]](../gfx/changebttn.png)
button in "Period Selection List" window,
"Period" window appears. It's for editing of the period data.
name,date,color,tag,description,url of the period data can be changed.
Delete Period Data
When the right-clicked menu item [ Delete This Period Data ] which the table item is selected is clicked, its data is deleted.
