Camera Slows as Approaches Keyframe

So I set a keyframe for a cameras position. Then move along in the timeline, moved the camera, set new keyframe, and vuala I have a simple animated camera movement.

However I noticed that as the camera leaves the first keyframe, it starts slow then speeds up. As it approaches the second, it slows down until it stops.

Why does it do that? And how can I fix it?

I’ve actually had this problem before, and fixed it, but I’ve forgotten. So can someone help me out?

Thanks!

With the Camera selected…
Goto the Graph Editor…
Hit ‘A’ to select ‘all’
Hit ‘T’ and select ‘Linear’
Your animation should now play at a constant speed…