No more month or year view

[Bbertatum]

Hello,

On a pretty vanilla setup (no tweaked options) the month and year view (for every metrics) does not show anymore.

This errors is thrown on CentOS 7 machine.

Following the error about time found i supposed the locale or something related is the problem there.

locale is like this on the machine :
LANG=fr_FR.UTF-8
LC_CTYPE="fr_FR.UTF-8"
LC_NUMERIC="fr_FR.UTF-8"
LC_TIME="fr_FR.UTF-8"
LC_COLLATE="fr_FR.UTF-8"
LC_MONETARY="fr_FR.UTF-8"
LC_MESSAGES="fr_FR.UTF-8"
LC_PAPER="fr_FR.UTF-8"
LC_NAME="fr_FR.UTF-8"
LC_ADDRESS="fr_FR.UTF-8"
LC_TELEPHONE="fr_FR.UTF-8"
LC_MEASUREMENT="fr_FR.UTF-8"
LC_IDENTIFICATION="fr_FR.UTF-8"
LC_ALL=

Any idea of what's going wrong ? You can find attached an example file generated and the error witch seems related.
Let me know if some more information is needed.

Regards

year_disk_.html.gz