JavaScript scroll speed

Hi All,

I’ve recently been working on a website, which features a horizontally scrolling frame on the right side. I have the horizontal scrolling mapped to the up/down of the mouse, so it can be scrolled in the same way a page is scrolled. My problem is, the scrolling is much to fast. I’d like it to be half the speed or less that what it is now.

Is it possible to slow this down, so the sensitivity isn’t as fast? If anyone has insight, or could point me in the right direction, it would be most appreciated.

The site, in it’s current version, can be found here:

Thanks in advance!