changing active side of worksheet in Excel 2007

[excelquest23]

Hello,

I'm working with a worksheet that previously had 300,000 rows of data but now only uses 25,000 rows. The vertical scroll bar on the right side remains tuned to the previously used 300,000 rows so is not very useful for moving up and down over rows 1 - 25,000.

Is it possible to reduce the active number of rows to 25,000 so that I can use the vertical scroll bar again??

Thanks,
Derek