On Saturday, 16 Dec 2017 at 19:24, Qiang Fang wrote:
> The last column is the ratio between column b and a, the last row is
> the sum of each row, the second formula only applies from the second
> row to the row before last row. The table that doesn't work is:
>
>     |     |      a |     b |      ratio |
>     |     |  0.797 | 0.780 |            |
>     |     |  0.744 | 0.730 |            |
>     |     | 12.707 | 2.384 |            |
>     | sum | 14.248 | 3.114 | 0.92040988 |
>     | ^   |      x |     y |            |
>     #+tblfm: $x=vsum(@2..@-1) :: $y=vsum(@3..@-1)
>     #+tblfm: $4 = ($3 / $2) * 100

I cannot help with the OP's question but this table leads to very
strange behaviour for me.  If I delete the tblfm lines, then go to the
location of the x variable (5th row, 2nd column) and type C-u C-c = to
enter "x=vsum(@2..@i-1)", that is okay.  But if I then go to the next
column and try to enter the equivalent formula for y, it replaces the
previously entered formula for x!  If I go back to the x location and
re-enter that formula, it replaces the y formula.

Further, the formulae created by org are missing the $ in front of the
variable, i.e. x=vsum(...) instead of $x=vsum(...).

This happens with up to date org from git as of an hour or so ago.

For the OP, the formulas

-- 
Eric S Fraga via Emacs 27.0.50, Org release_9.1.4-214-ge8b71b