Returns how marketing spend turns into revenue. It includes overall figures (leads, conversions,
revenue, marketing cost, return on investment, cost per lead and per conversion), the same figures
for each lead source and each campaign, a conversion funnel with the rate from each step to the
next, monthly performance, the best and worst performing campaigns, and a cost efficiency analysis.

Pick the period with start_date and end_date, or with a preset range. Without either, the
report covers the last 90 days.

The token's role must be owner or admin.