Counting backtracks

Dear all,

  I'm writing an optimization program in ECLiPSe
  and I'd like to count the total number of backtracks
  that happened until the optimal solution is found.

  I'm optimizing with the following predicate:

  minimize(search([Q001, Q002, Q003, Q004, Q005, Q006, Q007],
	   0,first_fail,indomain,complete,[backtrack(Back)]),Cost).

  But I feel that what I get in the variable Back is going to
  be only the number of backtracks that occurred between the
  next-to-last and last solutions.

  What would be the correct way to do this?

  Thanks a lot in advance.

Best,
Tallys

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  Tallys Hoover Yunes
  PhD student in Operations Research
  GSIA, Carnegie Mellon University, USA
  tallys@cmu.edu
  www.andrew.cmu.edu/~thy
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