Past studies suggest that repeats are a common feature of eukaryotes unlike the prokaryotes and archaea. Other reports suggest that irrespective of the comparative shortage of repeat elements in prokaryotic genomes, they nevertheless contain hundreds or even thousands of large repeats.   Current genomic analysis seem to suggest the existence of a large excess of perfect inverted repeats in many prokaryotic genomes as compared to eukaryotic genomes.
For quantification and comparison of inverted repeats between several species, namely on archaea, see