The average vocabulary of the average person in their NATIVE TONGUE is just over 3500 words (it varies a lot from culture to culture).
The average vocabulary of a University Graduate in the Arts is 10-12000 words. In the sciences it varies greatly, chemistry, biology and medicine being the most demanding at >15,000.
Someone with a vocabulary of 20-25000 words would be highly educated or very well read, or an specialist in a field.
If you have a Japanese vocabulary of 8000 words, you already have a bigger vocabulary than 74.13% of the population (if you understand what that percentage represents, you already have a larger vocabulary than the majority of people).
I don't know where you got that idea from, but I took an online test for English (which is my native language) vocabulary, and found that I knew about 30000 words. And I wouldn't consider myself to be that unusual.
The average vocabulary of a University Graduate in the Arts is 10-12000 words. In the sciences it varies greatly, chemistry, biology and medicine being the most demanding at >15,000.
Someone with a vocabulary of 20-25000 words would be highly educated or very well read, or an specialist in a field.
If you have a Japanese vocabulary of 8000 words, you already have a bigger vocabulary than 74.13% of the population (if you understand what that percentage represents, you already have a larger vocabulary than the majority of people).