TabRatio Property
Returns or sets the ratio of the width of the workbook's tab area to the width of the window's horizontal scroll bar (as a number between 0 (zero) and 1; the default value is 0.6). Changing the value of this property has an inverse effect on the length of the window's horizontal scroll bar. Increasing this property from the default value decreases the length of the scroll bar, while decreasing this property from the default value increases the length of the scroll bar. Read/write Double.
expression.TabRatio
expression Required. An expression that returns a Window object.
Example
This example makes the workbook tab half the width of the horizontal scroll bar.
Spreadsheet1.ActiveWindow.TabRatio = 0.5