Stacked bar graph negative values

Hi,

I found again that negative values ​​appeared for the current month when viewing stacked bar charts.
After some investigations, I noticed that this happened when the day of the UTC date is greater (+1) than the day of the local date (see the two screenshots taken less than a minute apart before and after the change of day in the local date).
My local time is UTC-10: 00 and after updating the settings, we find this date in the server information server and MySQL (see the server information copy).
I also found that the negative values ​​of the current month are exactly the sum of the values ​​of the previous months, but negative.
Is there another location where I need to set the local date to fix this display problem?
I also notice that the display returns to normal when the day of the local date becomes identical to that of the UTC date.

Server Information
Emoncms Version low-write 9.9.5
Modules Administration : App v1.2.0 : Backup v1.1.5 : EmonHub Config v1.0.0 : Dashboard v1.3.1 : Device v1.2.0 : EventProcesses : Feed : Graph v1.2.1 : Input : Postprocess v1.0.0 : CoreProcess : Schedule : Network Setup v1.0.0 : sync : Time : User : Visualisation : WiFi v1.3.0
Git URL GitHub - emoncms/emoncms: Web-app for processing, logging and visualising energy, temperature and other environmental data
Git Branch * stable
Buffer loading…
Writer Daemon is running with sleep 60s
Server OS Linux 4.14.71-v7+
Host emonpi emonpi (192.168.1.41)
Date 2018-11-21 14:13:06 HST
Uptime 14:13:06 up 1 day, 16:07, 0 users, load average: 1.69, 1.69, 1.65
HTTP Server Apache/2.4.25 (Raspbian) HTTP/1.1 CGI/1.1 80
MySQL Version 5.5.5-10.1.23-MariaDB-9+deb9u1
Host 127.0.0.1 (127.0.0.1)
Date 2018-11-21 14:13:06 (UTC -10:00‌​)
Stats Uptime: 144408 Threads: 2 Questions: 3918 Slow queries: 0 Opens: 26 Flush tables: 1 Open tables: 20 Queries per second avg: 0.027
Redis Version 3.2.6
Host localhost:6379 (127.0.0.1)
Size 57 keys (808.73K)
Uptime 1 days
MQTT Server Version Mosquitto 1.4.10
Host localhost:1883 (127.0.0.1)
Pi Model Raspberry Pi 3 Model B Rev 1.2 - 1 GB (Sony UK)
SoC Broadcom BCM2835
Serial num. 49978739
Temperature CPU: 68.76°C - GPU: 68.8’C
Release emonSD-30Oct18
File-system Current: read-write - Set root file-system temporarily to read-write, (default read-only)
Memory RAM Used: 17.61% Total: 976.74 MB Used: 171.97 MB Free: 804.77 MB
Swap Used: 0.00% Total: 100 MB Used: 0 B Free: 100 MB
Disk Mount Stats
/ Used: 39.80% Total: 3.81 GB Used: 1.52 GB Free: 2.12 GB
/boot Used: 51.78% Total: 42.52 MB Used: 22.02 MB Free: 20.5 MB
/home/pi/data Used: 5.03% Total: 3.21 GB Used: 165.11 MB Free: 2.88 GB
PHP Version 7.0.30-0+deb9u1 (Zend Version 3.0.0)
Modules apache2handler : calendar v7.0.30-0+deb9u1 : Core v7.0.30-0+deb9u1 : ctype v7.0.30-0+deb9u1 : curl v7.0.30-0+deb9u1 : date v7.0.30-0+deb9u1 : dom v20031129 : exif v7.0.30-0+deb9u1 : fileinfo v1.0.5 : filter v7.0.30-0+deb9u1 : ftp v7.0.30-0+deb9u1 : gd v7.0.30-0+deb9u1 : gettext v7.0.30-0+deb9u1 : hash v1.0 : iconv v7.0.30-0+deb9u1 : igbinary v2.0.1 : json v1.4.0 : libxml v7.0.30-0+deb9u1 : mbstring v7.0.30-0+deb9u1 : mcrypt v7.0.30-0+deb9u1 : mosquitto v0.4.0 : mysqli v7.0.30-0+deb9u1 : mysqlnd vmysqlnd 5.0.12-dev - 20150407 - $Id: b5c5906d452ec590732a93b051f3827e02749b83 $ : openssl v7.0.30-0+deb9u1 : pcre v7.0.30-0+deb9u1 : PDO v7.0.30-0+deb9u1 : pdo_mysql v7.0.30-0+deb9u1 : Phar v2.0.2 : posix v7.0.30-0+deb9u1 : readline v7.0.30-0+deb9u1 : redis v4.1.1 : Reflection v7.0.30-0+deb9u1 : session v7.0.30-0+deb9u1 : shmop v7.0.30-0+deb9u1 : SimpleXML v7.0.30-0+deb9u1 : sockets v7.0.30-0+deb9u1 : SPL v7.0.30-0+deb9u1 : standard v7.0.30-0+deb9u1 : sysvmsg v7.0.30-0+deb9u1 : sysvsem v7.0.30-0+deb9u1 : sysvshm v7.0.30-0+deb9u1 : tokenizer v7.0.30-0+deb9u1 : wddx v7.0.30-0+deb9u1 : xml v7.0.30-0+deb9u1 : xmlreader v7.0.30-0+deb9u1 : xmlwriter v7.0.30-0+deb9u1 : xsl v7.0.30-0+deb9u1 : Zend OPcache v7.0.30-0+deb9u1 : zlib v7.0.30-0+deb9u1
Client Information
HTTP Browser Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/11.1.2 Safari/605.1.15
Screen Resolution 1680 x 1050
Window Size 1306 x 897

Hello @Gerard1, usually the procedure to avoid this error is to ensure that the timezone in the My Account section matches that of your browsers timezone:

image|50%

I assume that has not solved the problem in this case? You should not need to edit timezone settings anywhere else. E.g the time on the raspberrypi itself should remain on UTC:

pi@emonpi:~ $ date
Thu 22 Nov 09:25:50 UTC 2018

Hi,

I may have made a setting error.
Indeed, at first start, the date displayed on the emonpi screen was on UTC.
Then I set of the timezone in the My Account section to match with my browsers timezone (see attached file).
After that, I modified the timezone in the raspberrypi using the following procedure and timezone on emonpi display shift to local timezone after reboot.
Is this correct?