How to change xticklabel or yticklabel style to Percentage?

Question

When using tikzpicture in the pgfplots package, how can I change use PERCENTAGE for xticklabel or yticklabel.

Here is a simple example:

\documentclass[a4paper]{article}
\usepackage{pgfplots}

\begin{document}
\begin{tikzpicture}
    \begin{axis}[
        xlabel=Cost,
        ylabel=Rate]
    \addplot[color=red,mark=x] coordinates {
        (2,0.003)
        (3,0.004)
        (4,0.005)
};
    \end{axis}
\end{tikzpicture}
\end{document}

How can I change the yticklabel to percentage style: i.e. 0.3%, 0.4%, 0.5%, etc.

I checked the documentation pdfplots.pdf and pdfplotstable.pdf. There are many Number Printing Settings available but I couldn't find anything that can covert the numbers to percentage style.

Thanks to all for your help! This is what I have right now. It still has problems.

\documentclass[a4paper]{article}
\usepackage{pgfplots}

\begin{document}
\begin{tikzpicture}
    \begin{axis}[
        xlabel=Cost,
        ylabel=Rate,
        scaled ticks=false,
        yticklabel=\pgfmathprintnumber{\tick}\,\%,
        yticklabel style={/pgf/number format/.cd,fixed,precision=3}]
    \addplot[color=red,mark=x] coordinates {
        (2,0.003)
        (3,0.004)
        (4,0.005)
};
    \end{axis}
\end{tikzpicture}
\end{document}

Answer 1

A collection of comments

\documentclass[a4paper]{article}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}
    \begin{axis}[
        xlabel=Cost,
        ylabel=Rate,
        scaled ticks=false,
        yticklabel=\pgfmathparse{100*\tick}\pgfmathprintnumber{\pgfmathresult}\,\%,
        yticklabel style={/pgf/number format/.cd,fixed,precision=2}]
    \addplot[color=red,mark=x] coordinates {
        (2,0.003)
        (3,0.004)
        (4,0.005)
};
    \end{axis}
\end{tikzpicture}
\end{document}