If you can replicate the total design conditions then you would be seriously the luckiest commissioning engineer on this planet.
You have to average everything and come up with +/- average performance figure. Generally if you are with-in 10% +/-, you are on the button and that should accepted by any half sensible consultant.
Good luck. If not acceptable ask for design conditions to be provided. Been there done that. Confussion is the best defence.