Returns a list of metrics for a transactional message in steps (days, weeks, etc). We return metrics from oldest to newest (i.e. the 0-index for any result is the oldest step/period).

You cannot request fewer than 2 steps of any period (2 hours, 2 days, 2 weeks, or 2 months). For instance, ?period=days&steps=1 means two days - the 48 hours before the API request was made. ?period=days&steps=0 returns the same as the maximum of the period - ?period=days&steps=45. See the steps parameter below for the maximum count of each period.