bal2-hmg9 hourly traffic in percent of capacity week 47 in 2021

/data/traffic/plot/plot-hr -n bal2-hmg9 -d 2021--47 -t traffic -f png  >/data/traffic/html/imgs/hr.traffic.bal2-hmg9.2021--47.png
Illegal division by zero at /data/traffic/plot/plot-hr line 97.
Plot failed, ret = 255