2.4.5 Why does Publish or Perish always count years until the current year, and not the indicated period?

Imagine you have just done a search (any search) with specific start and end years, for example from 2000 to 2005. However, the results do not show "6 years active" as you expected, but "11 years active" (if the search is done in 2010). What's going on?

The simple answer is that the search period (2000 to 2005 in the example) restricts the original publications. It does not restrict the citations. Regardless of the start and end years in your query, the results will always show the citations until the present day, give or take a few weeks. And because Publish or Perish shows citation statistics, we must count all years from the start year until the present day. Publish or Perish does not have control over this aspect of the results; it's Google Scholar that provides these data.