after updating to WP 3.9 I had to deactivate and reactivate all my plugins due to some tinymce issue. After reconnecting the jetpack plugin my previous stats were all gone.
I've read some others had the same issue and sometimes this was caused by the WP install being moved. This also applies to me, however I've moved my WP install more than a year ago. It was at http://www.klaasnienhuis.nl/wordpress, now the homepage is at http://www.klaasnienhuis.nl
How can I get my old stats back?