I have an interesting situation.  I am looking to model a 60 ton (720,000 Btu/hr) WSHP.  The tables 6.8.1 in 90.1 do not identify the efficiency ratings for a WSHP in cooling or heating mode above 135,000 Btu/hr cooling capacity. 

Since the units in question are much larger, what should I use for an efficiency rating?

Thank you,