Thread: how to interpret new BC's

recent trend in several projectile manufacturers is to publish multiple values for BC (G1 & G7) based on velocity.
eg Hornady now publishes “200 yard” Mach 2.25 (2,512 fps @ ICAO Standard Atmosphere**) G1 and G7 Ballistic Coefficient (BC) numbers for all A-TIP, ELD-X, and ELD Match bullets. Mach 2.0 (2,233 fps @ ICAO Standard Atmosphere) and Mach 1.75 (1,954 fps .
And state " values at Mach 1.75 (1954 fps @ ICAO Standard Atmosphere), should be used when calculating trajectories for shooting beyond 600 yds."

My question is for calculating long range eg 1000 yards, have Hornady already used an average of the 3 values and time in flight to come up with the Mach 1.75 value ?
or should you derive an average yourself based on
x% at Mach 2.25 + Y% @ Mach 2.0 + Z% @ Mach 1.75 ?