Customers
Lead sources and the funnel report
Where new leads came from and how many joined, the funnel stage by stage, and why leads were lost.

CustomersRead it in the appThe same article opens from Help inside app.dotask.io, beside the screen it describes.
Leads → Sources counts new leads in the period by where they came from (the source on their record, else the channel they first wrote in on) and how many joined, with joined for each new lead.
Leads → Funnel report shows, for the period, how many reached each stage, how many of those moved on, and the usual stay in each stage, plus the trial to joined rate and why leads were lost.