[Orgmode] clocktable display format

[Olivier Schwander]

Hello,

I am using clocktable to display a summary of the effort in a subtree.
As I am not particularly interested in precise hourly details, I would
like to display the total time in days instead of hours.

Now I have:
| L | Headline              | Time     |        |
|---+-----------------------+----------+--------|
|   | *Total time*          | *528:00* |        |

and I would like:
| L | Headline              | Time     |        |
|---+-----------------------+----------+--------|
|   | *Total time*          | *22*     |        |

I tried to add a formula in the table, but it doesn't work since the
fields are in the format hour:minute. I suppose I could use org-babel to
parse the content of the field and convert it into days but it seems
rather complicated and I would be happy with a simple solution. Any
ideas ?

Thanks,

Olivier