I have a MIDI composition, a number of tracks, with a lot of tweaks to the tempo all through the song.  I'd like to slow the whole thing down by a percentage, say 10 percent, but still preserve all the changes to the tempo throughout the song.  Simply changing the beginning bpm won't work because there are too may tweaks that change the tempo all through the song.  Is there a way to simply scale the tempos by a percentage?
Sorry if this is something basic- I'm still learning.

Open the Tempo view, click the Tempo List icon. Double-click each tempo in the list and change by 10%.
That's in SONAR X3.

Have you tried using the "fit to time" process and selecting Tempo Map under "Modify by Changing"?

Kronosman
Have you tried using the "fit to time" process and selecting Tempo Map under "Modify by Changing"?

This actually works, thanks! It's something I've wanted to do for a while and never thought to look there.
 
You have to select all tracks and then be sure to enter the complete time value hh:mm:ss:xx

Thanks for the responses.
The "Fit to Time" using "Tempo Map" worked very well, although it seems to affected some of the note characteristics in some way that I'll have to investigate.  There are over 700 tempo events, so anything to avoid changing each one is a big improvement!

dhartley1000
Thanks for the responses.
The "Fit to Time" using "Tempo Map" worked very well, although it seems to affected some of the note characteristics in some way that I'll have to investigate.  There are over 700 tempo events, so anything to avoid changing each one is a big improvement!

Maybe if there are controllers or other MIDI data they did not follow their original notes to their new locations?
 
Like they did not get included in the selection portion of the process.
 
BTW that is a very cool bit of info, Kronosman. I like yours too Gregy.

Unfortunately, Sonar does not have "Scale Tempo" feature.
http://forum.cakewalk.com/Tempo-Scale-m888655.aspx
http://forum.cakewalk.com/Scale-Tempo-m2431814.aspx
http://forum.cakewalk.com/Once-again-Scale-Tempo-m3219346.aspx

I was going to mention previously about a semi related topic...
 
Sonar acquired the ability (in the 2015 release) to "time stretch/warp" MIDI clips like we can with audio clips.
 
I think the procedure is the same. You hover over the end of a clip (in this case a MIDI clip) until the Smart Tool turns into the Crop Tool, hold the Alt Key then drag the clip boundary.
 
That stretches the clip by a %. If you have Snap enabled that will snap the end of the clip to beats/measure/etc.
 
I have no idea how that would apply to this type of thing if at all and across more than a few tracks it would be too annoying but it's an interesting feature and might help other people searching this topic figure out something that has not gotten a lot of attention.
 
Totally OT. Not helpful to OP (likely). Just thinking of the googly mooglers.
 
Cheers.

The only way to scale all tempo events proportionally is "Fit To Time", but it's trial-and-error. There is no percentage or "old BPM - new BPM" option.

Seven hundred!
Yeah, that would take awhile with my method.