Complex sentence: His precise reign length is unknown because different copies of Manetho's records credit him with a reign of 41 to 46 Years; some Egyptologists have proposed increasing the 41 year figure by a decade to 51 years to closely match Psusennes known historical dates.
Split into simpler sentences: His precise reign length is unknown because different copies of Manetho's records credit him with a reign of 41 to 46 Years. Some Egyptologists have proposed increasing the 41 year figure by a decade to 51 years to more closely match Psusennes' known historical dates.