repeated _\markup{} at same distance from staff...?

[B~M]

Dear ALL, at the risk of great embarrassment, I cannot seem to find what must be a simple 

command to set _\markup{} at a constant offset from the staff, rather than following the music 

up and down etc. I've attached my example which is a simple SATB harmony showing only the Soprano and 

Bass. The chord indications (shown int he first bar only) are the symbols I want to all be at the same distance from the 

staff, not the notes. 

There seems to be functions to do this for dynamics to be offset a constant distance from the staff, but I could 

not find a similar command for _\markup (or alternatively ^\markup{}). 

Any examples or pointers to the manual ?

Paul 

HarmQnExamMay2012-2.ly
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