Joined: Jul 2002
Posts: 40,863
Likes: 3,115
From: Sacramento, California, USA
Bikes: Specialized Tarmac, Canyon Exceed, Specialized Transition, Ellsworth Roots, Ridley Excalibur
It's 6 degrees from perpendicular (90) and can be flipped either up (90 + 6 = 96) or down (90 - 6 = 84). The 6 degree stem seems to be the most common angle for commuting, but I am sure you can get higher angle stems.
Why do you want to switch it?