sh_ and ch_ compose the same words

[ReneZ]

Torsten is correct in stating that the calculation of R assumes that the data is normally distributed.

I would love to see a reference for that.

If two quantities are fully correlated, their observations are on a straight line, and this is completely independent of their distribution.

Even if one were to feel more comfortable about computing the correlation of two normally distributed quantities, I would (again) like to point out that the distribution of the word counts as originally proposed by Torsten is very far from normally distributed (probably the furthest away), with all values being positive and the mass of them for small counts.
On the other hand, the quantity defined by nablator is significantly more similar to normally distributed. The correlation values computed from it are very close to those computed from the percentages.