I'm looking for the lengths of the centromeres of human chromosomes.
The best I could come up with so far has been: The length of individual centromeric arrays was found to range from an average of 680 kilobases for the Y chromosome to 3000 kb for chromosome 11.
Here they say that "Human centromeres are located at repetitive alpha satellite DNA arrays that compose approximately 5% of the genome." Which unfortunately is not the same as saying the centromeres compose 5% of the genome. (Or maybe it is? Biologists to the rescue!)
Ideally an answer would contain the length of the centromere in each chromosome, but a precise percentage for the whole human genome would be good enough.