How do I calculate the accuracy of 4284A when the desired stimulus is RMS current rather than RMS voltage?

The Keysight 4284A data sheet provides measurement accuracy as a function of stimulus level in rms volts (V_RMS). The equivalent RMS current (I_RMS) can be computed via the equation:

I_RMS = V_RMS / Z, where:

I_RMS = calculated equivalent RMS current;

V_RMS = V_RMS indications in the 4284A data sheet;

Z = Characteristic output impedance of the 4284A = 100Ω