AD7779 and AD7770


I have a question about a differencis of digital flter between AD7770 and AD7779.
Attached file is the rms noise and resolution performance table from the datasheet.
AD7779 and AD7770 have same combination of ODR and Decimation Rate excluding 32kSPS ODR of AD7770. Then I expect that I can get same band width. But there are a little defferencis band width between AD7770 and AD7779.
I'd like to know why does not have same characteristics of the digital filter.

Best regards,