autorotate - How to set the SPEED?

Hello dear forum members,

I guess this is the code for starting the panoramas with autoroation:

<action name="startup">
if(startscene === null, copy(startscene,scene[0].name));
loadscene(get(startscene), null, MERGE);

delayedcall(10, rotatestart());
delayedcall(3, showMenu() );
</action>

How does one set the speed of the rotation (I want to make it slower) ?

Any help will be greatly appreciated.

Best regards
Burak

Thank you very much Tuur,
This was very helpful .
Regards
Burak