I want to record the traffic on Pdf every 3 hours

RouterOS Scripting
1

Hi everybody;
I want to record the graph every three hours in mikrotik Can I?
or Is there a program that can record the graph every 3 hours and gives min traffic and the Max traffic in those three hours?

2

The Dude can do that. There is an interval Export setting which can save PDF

3

I have searched a lot but I did not know how to do this.
Can give me some steps?