\documentclass{article}
\usepackage{lmodern}
\usepackage{pgfplots}
\usepackage{lipsum}
\pgfplotsset{compat=1.9}
\usetikzlibrary{external}


\tikzexternalize

\begin{document}
\lipsum
\begin{center}
    \begin{tikzpicture}
        \begin{axis}[
            ybar stacked,
            ymin=0, ymax=35,
            width=9cm,
            height=6cm,
            symbolic x coords={Zimbabwe, France, Italy, Kenya, Germany},
            xtick=data,
            bar width=15pt,
            axis lines*=left,
            ytick={0,5,...,35},
            xticklabel style={
                text height=1.5ex,font=\footnotesize
            },
            yticklabel style={
                font=\footnotesize
            },
            ymajorgrids,
            xlabel={ ... ... ... ... ... , 2004-2009},
            xlabel style={yshift=5.8cm,xshift=.9cm},
            ]
            \addplot[fill=gray!50] coordinates {
                (Zimbabwe,16)
                (France,30)
                (Italy,10)
                (Kenya,5)
                (Germany,20)
            };
        \end{axis}
    \end{tikzpicture}
\end{center}
\end{document}
