Emacs Orgmode表$＆gt;参考不起作用

Question

GNU Emacs 24.4.1 org-mode

这是一个组织模式表

#+TBLNAME: revenue
| /       | <        |           | <        |                  | <    |       |         |        |            |           |      |       |        |       |         |       |
| Product | Year_SUM | Month_SUM | Platform | Platform_SUM     | adwo | AdMob | adChina | adSage | appfigures | appdriver | coco | Domob | Dianru | Limei | guohead | youmi |
|         |          |           |          |                  |      |       |         |        |            |           |      |       |        |       |         |       |
|---------+----------+-----------+----------+------------------+------+-------+---------+--------+------------+-----------+------+-------+--------+-------+---------+-------|
| Jan     |          |           | iOS      | #ERROR           | 1    |     1 |       1 |      1 |          1 |         1 |    1 |     1 |      1 |     1 |       1 |     1 |
|         |          |           | Android  | =vsum($6..$>);NE |      |     1 |         |      1 |            |         1 |      |     1 |        |     1 |         |     1 |
|---------+----------+-----------+----------+------------------+------+-------+---------+--------+------------+-----------+------+-------+--------+-------+---------+-------|
|         |          |           |          |                  |      |       |         |        |            |           |      |       |        |       |         |       |
#+TBLFM: $5=vsum($6..$>);NE

如您所见，公式$5=vsum($6..$>);NE无法计算！这是调试信息：

Substitution history of formula
Orig:   vsum($6..$>)
$xyz->  vsum($6..$>)
@r$c->  vsum($6..$>)
$1->    vsum((0)..$>)
        --------^
Error:  Expected `)'

但如果我用$5=vsum($6..$17)替换公式然后它可以工作，我无法弄清问题在哪里？

我需要一些帮助，欣赏它！