When using a pacing period, it’s important to map the measurements correctly. For example, if you map impressions or clicks, their type is Integer. However, mapping an Integer type can result in the calculation being rounded down. You can avoid miscalculations by using a delivery custom metric.
For example, you have 400 impressions for January 2018 and you’re using pacing to spread the impressions over the month. When you calculate the impressions per day (400/31=12), the results aren’t correct because 12*31=372, so you’ve lost 28 impressions. The results are even more incorrect when working with a smaller amount of data.
However, if you use the Delivery Custom Metric instead, which is a Double type, the data is correct.
This is how the data appears.
