Getting back mileage gross value on creation?

Hi API-team,

To create a mileage expense I specify the mileage only (not gross value) in
my POST request. On successful creation, I get back (in the header of the
response) the new expense id. Would be handy for the calculated/assigned
gross value to be returned also (in the response) for my local copy of the
expense.

Would this be possible and something that could be added to the API
functionality?

I guess I could send a GET request following my POST request or calculate
the gross value within my app but that seems a bit wasteful and redundant.

Regards,
Adil