Not so recently somebody posted a link to a dictionary that displays the frequency of a word. Well, I just forgot its name.
Of course there exists Duden, which however classifies words only in six possible levels of use. That dictionary I saw gives a better output and and takes as reference the word der (I don't say the 'article der', because I'm not sure they take the word as only meaning the article). Hence the output has, among otheres, the line:
<Input word>. Index: 6
and that means,
<Input word> is used about 2–6=1/64 times as often as der.
Could somebody refresh my memory?