I created a custom report to track the conversion rate for three goals. Everything looks good, except that if I view by week, conversion rates show zero for all weeks that spans two months (e.g. 24 Feb - 01 Mar, or 30 Dec - 05 Feb). If I change the report to show the days in question (day report for 01 Mar), all days in that week show a positive conversion rate.
So I wonder if there’s a math error somewhere in the report.
A similar report showing conversions (numbers rather than rates) seems to calculate correctly over the same periods. (Well, non-zero, at least. )