Cumulative conversion rate by day

Traveloka's experiment dashboard shows a running conversion rate so the team can watch a test unfold. Watching it is also how teams talk themselves into stopping early on a day that happens to look good — the false-positive rate climbs every time you peek and act.

From daily_ab, return day, variant, and cumulative_rate — total conversions through that day divided by total users through that day, rounded to 4 decimal places. Order by day, then variant.