select ABS (SUM) question

i have a survey that dumps the results to a mysql database....fome time to time we will have anywhere from 12 responses to over 700+. the survey choices range from 1-6 with six being highest (1-6 = very dissatisifed - very satisfied)

one of the survey metrics is "give me % for all those answers 3 (satisfied) or higher" which in mysql translates to:

SELECT ABS( SUM( Q1 >3  )  /21  )...etc.

as i have the query right now it works great...the problem lies in the fact, as stated earlier...the number of responses varies each time and the "/21" of the query SELECT ABS( SUM( Q1 >3  )  /21  ) will change often....without having to go and rewrite the query each time...is there a way to use the COUNT feature in mysql to populate the "/XXX" part of the query?

thanks


full query
------------------------
SELECT ABS( SUM( Q1 >3  )  /21  ) , ABS( SUM( Q2 >3  )  /21  ) , ABS( SUM( Q4 >3  )  /21  ) ,ABS( SUM( Q5 >3  )  /21  ),ABS( SUM( Q6 >3  )  /21  ),ABS( SUM( Q6 >3  )  /21  )  
FROM metrics