With this setting, you can adjust the transparency of the series value label background lines (label borders) using a value between 0 and 100. The default value for this property is 40.

Higher opacity will make the border more pronounced.

• 0%: The border will be completely transparent.
• 50%: The border background will be semi-translucent.
• 100%: The border will be completely opaque.

This setting is applied only to the series value label background line (label border). If you wish to change the opacity of the entire label background, use the Background Opacity setting.