Excel 2010 supports AutoMin and AutoMax that work something like: nMin = std::min<double>(nOldMin, 0); nMax = std::min<double>(nOldMax, 0); They are the default for Excel2010 data bars. Also excel 2010 import needs to be adjusted.
Markus Mohrhard committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/core/commit/?id=06aeaad3d1ec55dafe985642ef2b34beef384012 implement AutoMin and AutoMax, fdo#50462
Markus Mohrhard committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/core/commit/?id=c467aa6f29a004b03c072bb89fa36b687daca9f3 implement the ui part for AutoMin and AutoMax, related fdo#50462
Implemented odf import/export, oox import, ui and model. Will be available in 3.7.0