FF&S gives you the option:
"Calculating Gs: Craft with the huge fuel requirements listed above require a separate mechanism for calculation of Gs, because the mass of the vessel is continually changing as fuel is consumed. As a result, thrust is measured not in Gs, but in tonnes of thrust (the thrust necessary to give 1 tonne of mass an acceleration of 1G).
Once the craft is designed, calculate its G value when fully loaded, and then calculate its G value at each 10% increment of fuel consumption. G value is calculated by dividing the thrust in tonnes by the total mass of the craft (including fuel) in tonnes. By dividing the total fuel endurance of the craft by 10, you can arrive at a useful approximation of its performance, which may, for example, be 10 minutes at 1.2 G, 10 minutes at 1.4 G, 10 minutes at 1.6 G, etc.
Next, determine how much thrust in G-hours each 10% increment of fuel generates. To do so, divide the minutes of the increment (10 minutes in the example above, but it can be any length) by 60. The resulting value is multiplied by the G value of that increment to determine the total G-hours generated.
Using the example above, the increment is 10 minutes. Dividing 10 by 60 yields a value of 0.167. Therefore, the first 10 minute increment will generate 0.2004 Ghours (which we'll round down to 0.20), the second will generate 0.2338 G-hours (rounded down to 0.23), the third will generate 0.2672 G-Hours (rounded up to 0.27), etc"
Especially since one of the examples is a Nexus 9Z U-plant putting out 194,400 EP. Which is just slightly more than a 1A P-Plant's 100EP. 
. I lean toward the chart being wrong.
