How can I recreate this report? -- Number of Potentials in each stage by month

How can I recreate this report? -- Number of Potentials in each stage by month

I found this on the Zoho blog but can't find out how to create the first report listed.

Specifically, I need to know dollar amount (instead of number of Potentials), and I need it by week rather than by month. Can anyone help?

Thanks,
Monica