# Too much whitespace in a table with spreadtab and unitx S

i made a table where latex creates a big white-space between 2nd and 3rd column. Is there a way to force latex to reduce the width or to let it choose a better width by itself? The numbers themselves in the third column are OK. Here is a MWE:

    \documentclass{article}
\usepackage{siunitx}

\begin{document}

fixed-exponent=-4, round-precision=2, round-mode=places]}}
\toprule
{@n1} & {@n2} & {@n2} \\
\midrule
88 & 4.3 & \STcopy{v}{b2/a2/a2/ln(a2)} \\
144 & 10 & \\
322 & 39 & \\
692 & 176 & \\
1498 & 922 & \\
3180 & 3846 & \\
\bottomrule

\end{document}


which looks currently like:

Options from the siunitx package like table-unit-alignment = left and table-number-alignment = left change either nothing or remove the exponential part of the number.

You can tell siunitx how much space it should reserve for the S columns by giving a suitable table-format.

\documentclass{article}
\usepackage{siunitx}
\usepackage{booktabs}

\begin{document}

fixed-exponent=-4, round-precision=2, round-mode=places, table-format=1.2e-1]}}
\toprule
{@n1} & {@n2} & {@n2} \\
\midrule
88 & 4.3 & \STcopy{v}{b2/a2/a2/ln(a2)} \\
144 & 10 & \\
322 & 39 & \\
692 & 176 & \\
1498 & 922 & \\
3180 & 3846 & \\
\bottomrule