As documented, the ->week() method is defined as follows:

The first week of the year is defined by ISO 8601 as the one which contains the fourth day of January, which is equivalent to saying that it's the first week to overlap the new year by at least four days.

Given that definition, I think your expectation is wrong, as that week belongs to week 53 of 2015.

If you want a different definition than what ISO 8601 defines, maybe say that the week number is the number of Fridays that have passed since (and including) the start of the year, then you will have to write some code.

In reply to Re: Another date question by Corion
in thread Another date question by sshingor

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