ESPP discount rate entry

Hi there,

 

While inputing my ESPP transaction, I am prompted to enter the "Discount percentage (i.e. 15% maximum)".

As you may know, it takes the 15% off of either beginning or the end of the period, which means that the actual discount value compared to the end of the period may be larger than 15%.

 

In the above case, do I input the actual discount value (my company provides this value), or just 15% fixed?