For instance 2015, 2016, 2017 as the year for each column
Read these guidelines and edit your questions. What are you trying to format? A table? In Calc or Writer? Don’t forget to mention your OS and LO version.
In Calc, choose Format - Print Ranges - Edit…, and select Rows to Repeat.
For Writer tables, choose menu Table - Properties… - Text Flow tab, check Repeat heading, OK.
Tested with LibreOffice 6.4.7.2 (x86); OS: Windows 6.1.
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