Or Excel::Writer::XLSX if you have the latest version of MS Excel and you want to write in it's native XML format.

You might want to do this go get around the limitations in the older Excel format (eg: maximum of 256 columns and 2**16 rows per sheet).

Both modules are written by the same author and claim to have the same interface, so you could decide which to use at runtime while only having a few lines of code that depend on which file format you plan to write.