Hi. In version 9.0.5 Org (Emacs 25.1) seems to generate too many columns in some situations. I'm not quite sure since which version this happens, in Org 8.x I have not seen this behaviour.
Here is a small example: --8<---------------cut here---------------start------------->8--- #+BEGIN: clocktable :maxlevel 3 :scope file :narrow 80! :compact #+CAPTION: Clock summary at [2017-02-18 Sat 12:37], for February 2017. | Headline | Time | | | |-------------------+--------+---+---| | *Total time* | *0:15* | | | |-------------------+--------+---+---| | Some Tasks | 0:15 | | | | \_ STARTED Task1 | 0:15 | | | #+END: * Some Tasks ** STARTED Task1 :CLOCK: CLOCK: [2017-02-18 Sat 12:00]--[2017-02-18 Sat 12:15] => 0:15 :END: --8<---------------cut here---------------end--------------->8--- It seems that the iteration over the items generates to many "|". And top level headlines (e.g. "Some Tasks") each generate one more "|" than their children (but even those seem to generate to many "|"). I did not fully understand the function org-clocktable-write-default, so I'm not quite sure how to best fix this. -- Until the next mail..., Stefan.