In PTARQ->determine approver alv report end date shown is 01.01.1997?

Hi experts,

going to tcode PTARQ->determine approver and giving personal number it shows approver details.In this alv report a field enddate is shown as 31.01.1997.where does it come from??Is this an error??How to solve this?(am i doing something wrong..?? i checked all the infotype values..enddate is 31.12.9999)

Regards