How to model data for line graph

[Sreejith]

Hi,

I push data through Rest Api for creating a line graph. The chart displays the average value against timestamp.

How should I model data in order to make such a report? 

The average will be calculated as follows;

avg = no of images / time taken to upload images in sec

This needs to be displayed in a line chart with timestamp along X-axis.

Any help please.