Hi Manish, That's curious. Your formula appears to be correct to me, so
perhaps it is related to the Is Active state of the Program -- more
specifically, Workfront might not allow such calculations on (e.g.
Status History II) on an object (e.g. Program) that is not Active,
choosing (e.g. As Designed) to instead "leave everything alone". I'd
suggest you do some testing to confirm, and/or contact support, who
might be able to explain their reasoning (or a workaround). Regards,Doug