can you help me understand why?

Because you use hard to read and highly convoluted code, and you try to do date calculations "by hand".

The recent thread Best way of getting YEAR-MONTH-DAY from YEAR-DAYOFYEAR ? covers some possibilities that look far nicer and seem to work.

In reply to Re: Number of day in the year to proper date by moritz
in thread Number of day in the year to proper date by gio001

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