How long ago did you reinstall your operating system
I could be wrong, but (and in my life I usually am) perhaps the number of events listed at the top of the right pane reflects the actual number of events that have been recorded over the last 7 days (if you have rewrite set at default)
Perhaps you left clicked the header for Type. Look under View and select oldest or newest
Are you viewing the Event Log from the MMC console
I'll admit I'm no computer genius or guru, so if my suggestions are off the mark, please keep in mind, that I was only trying to help. Even if my help was not of much help at all
I wish you luck finding a solution
