Hotkey for insert equation to word 2010

It's not so convenient to go to insert --> equation --> insert new equation everytime you want to create a new one. I guess there must be some hotkey to insert an inline equation at the current cursor position? However, Microsoft Office Help doesn't help (as usual). I tried google it but there aren't any solution work.


It's "Alt+=", but it only works in docx files and you should have VB-component installed to enable macros.