At 9/22/2015 10:25, you wrote: > Another dumb question: does the TMG date calculator tool (or >others) take into consideration leap years and the month of February?? > > Distant cousin-in-law died 15 Apr 1864 (a leap year), aged 50-1-24. >Date calculator calculates his birth date as 22 Feb 1814, but that >seemed wrong to me--even assuming 28 days for Feb., then based on 22 >Feb to 15 Mar, well, that's just 21 days, not 24; throwing in the leap >year, well, then that's 22 days. So ... seems to me he was probably >born 20 Feb 1814, that is, 9 days in Feb. plus 15 days in March equals >24 (March) and adding one month, brings us/me to Apr 24 > > Am I overthinking this?? (Or hah, showing my poor math skills??) >Does anyone know if waaay back then did they even worry about February >not being 30 or 31 days, or for that matter leap years? You asked the right question there. Trying to determine a date from one date and the number of day/months/years requires that you know how those days/months/years was calculated. As John Cardinal says, the usual method is start from days and go to years. Most date calculation methods ignore leap year unless dealing with a known leap year. Further, if conversion of days is needed (subtracting a larger number of days from a smaller, or adding days to more than a month), what value is used to make the conversion -- 28, 29, 30 or 31? Most only add/subtract 30 days and let it go. But, we usually don't know what someone else did. About all we can do is calculate dates is see what the result is. If the result is reasonable based on other evidence, that is the date I use. For example, I know a death date, and the age in days/months/years. I also know from a family legend that the person was born three days before a documented event. So if the date calculation result gives a date three dates before the documented date then I know the calculations are right. On the other hand, because of the documented event, I probably didn;t need to do the date calculation anyway. <g> Lee