Cynthia, I can confirm that LibreOffice can read and create XLSX files directly, and I do use that facility on a regular basis, but there are public organisations, and even governments, internationally that have standardised on the OpenDocument file formats. I've done a fair amount of investigation into the structure and contents of XLSX and *.ods files, and concluded that the Open Source *.ods files, which can also be read by newer versions of Excel, should be smaller and hold more precise numeric values (including dates and times) than the equivalent XLSX files. Surely it would be better to support an Open Source file format, than a proprietary one, especially when it has size and precision advantages, and no readability issues? ........Phil
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