To align estimates, three steps were taken. First, operators were requested to calculate a daily OEI estimate so that individual operating states could be extracted. Operators also provided a log of when compressor units were operating and/or pressurized. This allowed the OEI to be decomposed into one OEI estimate for each operating state. Note that OEI estimates are assumed constant for each operating state; this eectively averages estimates for variable emitters (e.g. intermittent pneumatics or dump valves on compressor interstage separators).