sum up variables from different org-mode tables

[Martin Gross <m-gross@gmx.net>]

Dear helpers,

I have a big file where I enter incomings and outgoings of book
exchanges with different institutions:

* Institution A
  |   | In      |  # |   € | Out     |  # |   € |
  |---+---------+----+-----+---------+----+-----|
  |   | Title P |  1 |  45 | Title A |  1 |  15 |
  |   |         |    |     | Title B |  2 |  28 |
  |---+---------+----+-----+---------+----+-----|
  | # |         |  1 |  45 |         |  3 |  43 |
  | ^ |         | TE | TEE |         | TA | TAE |
  #+TBLFM: $TE=vsum(@I..@II)::$TEE=vsum(@I..@II)::$TA=vsum(@I..@II)::$TAE=vsum(@I..@II)

* Institution B
  |   | In | #  |  €   | Out | #   | €   |
  ...
  | # |    |  1 |  24  |     |  2  | 31  |
  | ^ |    | TE | TEE  |     | TA  | TAE |

Now I would like to get some statistics that consider all institutions
together.  For example summing up the "variable" TAE from all the
tables in the file to get the very total cost of outgoings.

Is something like that possible?

Thank you very much in advance!

Martin