What constitutes a food safety or food quality trend?

For SQF Facilities - Can anyone tell me what constitutes a food safety or food quality trend and how is this supported ?   For example, is a trend more than twice in a one month period based on product volume?  

I think this depends on your site/activity/history.  eg. we have one European site in the food group I work for that has high foreign body counts (EVM) but this is due to where they source their fruit from (small producers in Europe) whereas our USA site has very few EVM issues as there is tighter control at producer level (FSMA) and suppliers are larger...... corrective actions are in hand for the European site!!

So, if I saw a lot complaints from our European site I'd understand why - if the same was true of the USA plant I would be worried....