Yes, because produce varies a lot in size. For a better idea of what you'll get, go by the weight recommended, and weigh the produce first.

This was a by weight recipe. I made some pickled squash that was by weight also and I got more than recipe said. I'm not complaining that I get more. Just curious.....

Lots of variables that can cause it - different measuring techniques, different chopping sizes, different jar packing (many tend to either under-pack or over-pack), etc.

The yields are only an approx. guideline but if the results are off by several jars either way then something was done wrong. Especially common when one tries to cut or double a recipe as it is easy to make mistakes with one ingredient or another.

Dave