[O] Mean of a column in a remote table

[Roger Mason]

Hello,

I _think_ this question has a simple answer, but I cannot find it.

I need the mean of a column in a remote table.  My current attempt looks
like this:

| Data              |     a |
|-------------------+-------|
| mic_2_in_648_cell |       |
#+tblfm: $2=remote($1,vmean(@2..@-1))

#+name: mic_2_in_648_cell
|         a |
|-----------|
| 28.886207 |
| 28.900981 |
| 28.886101 |
| 28.900659 |
| 28.900526 |
| 28.886694 |
| 28.886559 |
|  28.90024 |
| 28.900524 |
| 28.900583 |
| 28.886496 |

The second column of the upper table is intended to receive the mean of
table 'mic_2_in_648_cell'.  Instead I get the error 'Row descriptor -1
leads outside table'.

This is a cut down example that captures the essence.

Thanks for any help.

Roger
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