The decrease in investigation reports could not be explained by the diminution in the number of cases reported to the Office of the Inspector General because the number increased between 2007 and 2008 (279 against 212).
调查报告数目减少可能是因为2008年向监察主任办公室举报的案件数目少于2007年(2007年为279起，2008年为212起)。