Chronologische Sortierung Im Literaturverzeichnis

% arara: pdflatex
% arara: biber
% arara: pdflatex
% arara: pdflatex
\begin{filecontents*}{\jobname.bib}
    @article{Greenwald.2013b,
        author = {Greenwald, Glenn and MacAskill, Ewen},
        date = {2013-06-07},
        title = {NSA Prism program taps in to user data of Apple, Google and others},
        url = {http://www.theguardian.com/world/2013/jun/06/us-tech-giants-nsa-data},
        urldate = {2016-07-08},
        journal = {The Guardian}
    }
    @article{Greenwald.2013e,
        author = {Greenwald, Glenn and MacAskill, Ewen},
        date = {2013-06-11},
        title = {Boundless Informant: the NSA's secret tool to track global surveillance data},
        url = {http://www.theguardian.com/world/2013/jun/08/nsa-boundless-informant-global-datamining},
        urldate = {2016-07-11},
        journal = {The Guardian}
    }
\end{filecontents*}
\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[ngerman]{babel}
\usepackage[babel=true,german=quotes]{csquotes} 
\usepackage[style=apa,backend=biber,language=ngerman,apamaxprtauth=99,sorting=nymdt]{biblatex}

\DeclareSortingScheme{nymdt}{
  \sort{
    \field{presort}
  }
  \sort[final]{
    \field{sortkey}
  }
  \sort{
    \field{sortname}
    \field{author}
    \field{editor}
    \field{translator}
    \field{sorttitle}
    \field{title}
  }
  \sort{
    \field{sortyear}
    \field{year}
    }
    \sort{
    \field{month}
    }
    \sort{
    \field{day}
  }
  \sort{
    \field{sorttitle}
    \field{title}
  }
  \sort{
    \field[padside=left,padwidth=4,padchar=0]{volume}
    \literal{0000}
  }
}
\DeclareLanguageMapping{ngerman}{ngerman-apa}
\DeclareFieldFormat{apacase}{#1}
\addbibresource{\jobname.bib}

\begin{document}

\nocite{Greenwald.2013b}
\nocite{Greenwald.2013e}

\printbibliography 
\end{document}