Note the Increasing ReTest. This means that we AVERAGE the HER from the Leak and the Increasing ReTest to calculate the emissions for that Interval.
This is a nonIncreasing ReTest. We use the previous, higher PPM to calculate the HER for the entire previous Interval. Note the Flat Line at the top of the colored area and the fact that the Ref HER, the Initial HER, the Final HER and the iHER for the previous Interval are all based on the Initial 3,000 PPM ReTest.