### What is the problem? In the callout in the [section about storing dates](https://librarycarpentry.github.io/lc-spreadsheets/03-dates-as-data.html#storing-dates), the link to the [1900 date system](https://support.microsoft.com/en-us/help/214330/differences-between-the-1900-and-the-1904-date-system-in-excel) is broken. ### Location of problem (optional) _No response_
What is the problem?
In the callout in the section about storing dates, the link to the 1900 date system is broken.
Location of problem (optional)
No response