The module "Email Stats" shows statistic graphics of the quantity of incoming emails.
The first graphic shows the amount of incoming emails of the last 26 hours and it is updated every hour. You will see this graphic from 3 hours later of installing this module.
The second graphic shows the amount of incoming emails of the last 7 days and it is updated every 6 hours. You will see this graphic from 13 hours later of installing this module.
The third graphic shows the amount of incoming emails of the last 12 months and it is updated every 15 days. You will see this graphic from 1 month later of installing this module.
The message "Nothing to show yet" means that PBX doesn't have the enough information to show these statistics.
Figure 1