Computes the time when the minimum value is reached for the first time in a period.
statistic = max_value_time
Computes the time when the maximum value is reached for the first time in a period.
statistic = min_value_time
Computes the difference between the first and last values within a period. If there are multiple adjacent periods, the function computes delta as the difference between the last values of adjacent periods.
statistic = delta
Similar to delta except for special processing of resets. Applicable for incrementing non-negative metrics. Reset occurs when the series value is lower than the previous value, in which case the counter adds the difference between 0 and the current value.
statistic = counter