Last Updated: 2021-08-23 (4 weeks ago)
If you open the Loinc.csv file (or any other files in the distribution containing the LOINC_NUM column) in Excel, the application will interpret several of the codes as dates. Excel thinks codes 1-8 through 12-5 are month/day abbreviations, i.e. "8-Jan" and "5-Dec". These codes can be retrieved via a SearchLOINC query (free LOINC login required).
The solution is to create a new Excel workbook file and then import the Loinc.csv, explicity choosing the "CSV file" option.