vertically align rotated text in table

Question

I have the following table (see code of working example below). In column 5 there are two cells that include some rotated text. I would like this rotated text to be centered or aligned at the bottom of the cell rather than having it shifted upwards. I've looked at the examples in this forums but couldn't find a solution so far. Any hints? Thanks.

\begin{table}\caption{ bababalbablab}
\begin{tabular}{p{3cm}p{3cm}p{3cm}p{3cm}p{0.25cm}}
\multicolumn{1}{c}{\bf{XXX}} & \multicolumn{3}{c}{\bf{XXX}} &  \\
\emph{Monday} & \emph{Monday} & \emph{Monday}  & \emph{Monday} &  \emph{Tuesday}  \\

{\bf July} (i.e. Monday, tuesday thursday) & {\bf August} (i.e. Tuesday Saturday Sunday) & {\bf September} (i.e. Sunday sunday sunday)& {\bf October} (i.e. Wednesday Wednesday Wednesday )&  {\rotatebox{90}{\emph {December}}}  \\
{\bf February} (i.e. Sunday Sunday Sunday Sunday )& {\bf January } (i.e. Friday Friday Friday)& {\bf March} (i.e. Thursday Thursday Thursday) & {\bf November} (i.e. Tuesday Tuesday Tuesday ) & {\rotatebox[origin=l]{90}{\emph {December}}}  \\

\hline 
\end{tabular}
\end{table}

Answer 1

With a convenient \raisebox, you can have the rotated text vertically centred. Please don't use the deprecated \bf. Use \bfseries or \textbf{…}:

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[showframe]{geometry}
\usepackage{tabularx, booktabs, rotating, caption}

\begin{document}

\begin{table}
  \caption{ bababalbablab}
  \setlength{\extrarowheight}{.5ex}
  \begin{tabularx}{\linewidth}{*{4}{>{\raggedright\arraybackslash}X}c}%>{\raggedright\arraybackslash}p{3cm}|}
    \toprule
    \multicolumn{1}{c}{\bf{XXX}} & \multicolumn{3}{c}{\bf{XXX}}   \\
    \cmidrule(lr){1-1}\cmidrule(lr){2-4}
    \emph{Monday} & \emph{Monday} & \emph{Monday} & \emph{Monday} & \emph{Tuesday} \\
    %
    \textbf{July} (i.e. Monday, Tuesday Thursday) & \textbf{August} (i.e. Tuesday Saturday Sunday) & \textbf{September} (i.e. Sunday Sunday Sunday)%
    & \textbf{October} (i.e. Wednesday Wednesday Wednesday)& \raisebox{-0.85\height}{\rotatebox{90}{{\emph {December}}}}
    \\\addlinespace
    \textbf{February} (i.e. Sunday Sunday Sunday Sunday )& \textbf{January} (i.e. Friday Friday Friday)& \textbf{March} (i.e. Thursday Thursday Thursday) %
    & \textbf{November} (i.e. Tuesday Tuesday Tuesday) & \raisebox{-0.85\height }{\rotatebox[origin=l]{90}{\emph {December}}} \\
    \bottomrule
  \end{tabularx}
\end{table}

\end{document}