This is my first attempt to define my own environment. I fail with the number of parameters. LateX complains Illegal parameter number in definition of endperformance. This should be a standard textbook example but I can't see what I am doing wrong.
\newenvironment{performance}[1]
{
\begin{table}[ht]
\begin{tabular}
{llllllll}
\toprule
{} & {Return} & {Annua Return} & {Volatility} & {Sharpe Ratio} & {Max DD} & {YTD} & {2015}\\
}
{
\bottomrule
\end{tabular}
\caption{#1}
\end{table}
}