Gradually slowing tempo

How do you accomplish a gradually slowing tempo that VIs will follow?
 
For example, I need an EZD track that gradually slows for the last 8 measures.  How would you do this?

It's easy as long as you're dealing entirely with unbounced virtual instruments. Start by determining what you want your final tempo to be and how many measures you want it to take to get there. It can be abrupt, gradual, or stepped.
 
The trick is drawing the changes such that the slowdown sounds natural, and that depends on the song. It may, for example, require multiple drops followed by 4- to 32-beat horizontal segments in between. Or it may call for one long, gradual line from starting tempo to ending tempo if you're after a classic ritard. It might need a gentle slope or a sudden drop - just avoid abrupt changes within a measure; such changes are usually more natural-sounding when they occur on the downbeat. I've gotten best results with many small changes, usually a 45-degree slope over a quarter-note's duration followed by a horizontal line for the rest of the measure (up to 4 measures).
 
The good news is the tempo map, like everything else in SONAR, has an undo stack, so you can experiment to your heart's content.

Thanks guys.  I don't know why, but I expected this to be tricky.  A quick line with the line tool and it's done.