Baffling births vs census

Question

I am trying to add proper citations for profiles I added back in the spring before I fully understood what was required.  This one particular family has me especially baffled and I wonder if others could review my research notes and see if they can make better sense of the sources I have found.  The 2 individuals are:

John SIM [Sim-864] and Janet ADAMSON [Adamson-3440].

Answer 1

The instructions to the census takers for the 1841 Scotland Census was that ages be rounded down to the nearest five for anyone over 15 years of age - although this instruction wasn't always followed. Also since the census is taken around mid year (1841 was taken June 6, The 1851 March 30), there can be a +- 1 year wobble in age in years vs birth years

https://www.nrscotland.gov.uk/research/guides/census-records/1841-census

https://www.nrscotland.gov.uk/research/guides/census-records/1851-census

Comments

Thank you Rob.  I do understand about the 5 year rule re 1841 census.  Hence my use of their age as 40-44 in my research notes.  However as Janet was born in 1783, she would be about 58 in 1841, much more than just moving down to the nearest increment of 5.  Nor does it explain how in 1851, she is shown as 64.  Her death registration would suggest a birth about 1785, which fits closely with her birth registration, so I assume 1783 is her correct birth date.

Husband John goes from 40 to 47 in 1851, so he then should have been 37 in 1841, but by using the rule of 5, 1841 should then have been shown as 35, not 40.  John according his death registration would have been born about 1793, or aged about 48 in 1841 and 58 in 1851. Thus, 1841 should have shown 45, not 40 and 1851 should have been about 58, not 47.  

I could just rule these out as transcription errors by FreeCEN but there's too many that are not even close.  My experience with FreeCEN is they are usually accurate

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People didn't necessarily tell the truth about their ages. In cases where the wife was older than the husband, he may have been unaware of her real age, or they didn't want the census taker to know. The case of being just 5 or so years older on the next 10 year census has happened several times in my research.

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I understand what you both are suggesting, but my thinking now is as follows, I only wish there was a way to confirm it.

Alexander ADAMSON [Adamson-3437] and Jean SKAKEL [Skakel-30] had a 2nd daughter named Jean ADAMSON [Adamson-3441] as per her 1787 birth registration. Janet and Jean are often a diminutive version of one another, so I think it odd that they would name their 2nd daughter Jean, unless Janet had died as an infant.  However I can't find any evidence of such a death.  Despite that, I now think Janet ADAMSON [Adamson-3440] had died and perhaps was not registered.  That would lead me to believe the wife of John SIM [Sim-864] was actually Jean ADAMSON [Adamson-3441] born 1787.  That date fits perfectly with the age 64 shown on the 1851 census. However it doesn't answer the question of John's age of 47, or why 1841 census has both their ages as 40.