Dear All, The subtraction method for calculating birthdates based on age goes a bit wonky (i.e. skew-if, wrong) in certain special cases. Consider this fairly simple example: Suppose the person died March 5, 1888, > at the age of 0 years, 0 months, 7 days. > ****Write the year, month, day as:-> 18880305 > ****Subtract the age at death:-------> 000007 > ****This gives the figure:---------> 18880298 > ****Now subtract 8870:---------------> 8870 > ****The result is:---------------- > 18871428 That's read as Year 1887, 14th month, 28th day. In normal language, that's 28th February 1888. Do a quick reality check: >From 28th Feb to 5th March is 6 days in a leap year (as 1888 was), but only 5 days in other years. Maybe the system, as related to the list, doesn't always work. Even using one's fingers, provided you have eight of them (and two thumbs) and know how to use them, you'd know that the person was really born the day before on 27th February 1888. Moral: Don't throw away your fingers or your commonsense. Can anyone find an error in this? Regards, Lex. Lex Johnson Queensland, Australia l.johnson@cqu.edu.au