How to generate chart model from audit data?

Hello,

I want to show chart like below image for Account (and Account audit) data:

(Above chart is basically from TFS showing Cumulative flow based on work item using history data.)

I want to generate similar chart with Account and it's History(Account audit) data. For e.g I want to show Number of account time wise. Could any one suggest me some idea to prepare model for chart?

Thanks,

Ashish