\begin{table}%t1
\caption{\label{grsdates}Observations of GRS~1915+105.} 
%\centerline
 {
\begin{tabular}{l l l}
\hline\hline
Year    &   MJD$-50~000^{a}$     & Subsets \\
\hline
2004    &   3123(4), 3124(4), 3125(3), 3126, 3127(3), 3128  & I, plateau \\
        &   3141(4), 3142                                   & I, post-flare \\
2005    &   3528                                            & \\
2006    &   3878, 3879(2), 3887, 3890(2), 3894              & II \\
        &   3964, 3967(2), 3969(2), 3970, 3974, 3975        & III \\
2008    &   4617(2), 4618(4), 4620(2), 4621(2), 4622(2), 4623(2), 4624(3), 4625(2), 4626 & IV, plateau \\ 
\hline
\end{tabular}}
\medskip
\par
$^a$ Figures in brackets indicate the number of independent observation segments ($\sim $28~min each) on a given night.
\end{table}