I have often read that the vocabulary of the English language consists of words of roughly 60% Latin origin and of roughly 40% words of Germanic origin, give or take. This to me seems accurate as a relatively crude approximation, as almost every English word can either be found in a modern Latin-based language like French or Spanish or in a Germanic-based language like German.
My question is: If I wanted to get crude, statistically provable results for the lexical origin in other languages, what would be the best way to go about it? It should be a process that can be automated.
Let's say for example I wanted to define the lexical origins of a language like modern Russian. What would be the best way to go about it?
I have found that what makes this hard to answer in a generalized fashion is, among other things, the fact that the result can highly depend on what kind of source material it is based upon. For example, if you were to analyze a text about medicine or technology in Russian, you may get the impression that Russian is Latin or English-based to a much higher degree than if you were to analyze texts about topics that use less homogenized vocabulary.
On the other hand, analyzing the entirety of a language's vocabulary might also result in skewed results, as that would include obsolete words, as well as highly technical and specific ones, again resulting in an output that may not accurately reflect the average use of the language. Perhaps it would then make sense to take into account all words of a language but apply a score to words that is based on their overall frequency?
What are good ways to go about measuring this? For instance, with the English example, how was this done? Because it does seem to relatively accurately reflect the reality for standard use cases.