Allowed min/max date ranges are depend on formatting pattern

[borgar]

The highest number allowed in Excel for a date is 2958465.99999999. Numfmt enforces this by checking if value >= 2958466 and erroring if this is the case. However, Excel errors beyond 2958465.99999421 when the format string isyyyy-mm-dd. Numfmt does not do this.

Likely, this is because Excel checks for errors after rounding for the format has occurred, but numfmt is testing the unchanged input value.

Here is a table of max values for formats:

format	max value	output
yyyy-mm-dd hh:mm:ss	2958465.99999421	9999-12-31 23:59:59
yyyy-mm-dd hh:mm:ss.0	2958465.99999942	9999-12-31 23:59:59.9
yyyy-mm-dd hh:mm:ss.00	2958465.99999994	9999-12-31 23:59:59.99
yyyy-mm-dd hh:mm:ss.000	2958465.99999999	9999-12-31 23:59:59.999