see www.manxnotebook.com/history/demog/as.htm - the IGI is a mess - some parishes having been fouled up more than others - I've been doing some work on German and there are several readings for same entry in the IGI - some have transcribed the year incorrectly, others 'modernized' spellings, some are just misreadings (Tanbman instead of taubman etc, Corris and Corrin are confused, Carin(e) in Arbory is often in danger of being recorded as cariin (Cowin is also in danger of being corrin (or vice versa). There are many Manx rewrites of names (eg O'niel to Nelson !), Gill to Kinry, Boyd and Boddagh,