Understand statistic options

If a content item or graphic has the Statistic property, you can choose to see the average, minimum, maximum, or last data value for the specified timeframe.

• Average

  CONNECT visualization uses a time-weighted average algorithm to calculate each data value shown.

  With the average, values are multiplied by the time difference between the points to determine the time-weighted value. So, the longer a stream had a particular value, the more weight that value holds in the overall average. The overall average is determined by adding all of the time-weighted values and then dividing that number by the total amount of time.

  Stair-step interpolation is used for the the time-weighted average. The formula is:

  ((P1 x (T2 - T1)) + (P2 x (T3 - T2)) + (P3 x (T4 - T3))) / (T4 - T1) = Average

• Maximum

  The maximum value from the actual data values within a retrieval cycle. If there are no actual data points stored on the historian for a given cycle, nothing is returned. NULL is returned if the cycle contains one or more NULL values.

  The number of cycles is based on the specified resolution or cycle count. However, maximum retrieval is not a true cyclic mode. Apart from the initial value, all points returned are delta points.

  Maximum retrieval only works with analog data. For all other data, normal delta results are returned.

• Minimum

  The minimum value from the actual data values within a retrieval cycle. If there are no actual data points stored on the historian for a given cycle, nothing is returned. NULL is returned if the cycle contains one or more NULL values.

  The number of cycles is based on the specified resolution or cycle count. However, minimum retrieval is not a true cyclic mode. Apart from the initial value, all points returned are delta points.

  Minimum retrieval only works with analog data. For all other data, normal delta results are returned.

• Last

  The final data value recorded for the timeframe you specify.