Can I estimate ring pll jitter by measuring ring VCO tuning voltage ripple?

After measuring loop filter output voltage : Vtune average and Vtune peak voltages for locked PLL

Calculation:
VCO average freq = Fvco_av [Hz] = Vtune_av [V] * Kvco[Hz/V];
VCO average period =Tvco_av= 1/Fvco_av [s]
VCO peak freq= Fvco_pk = Vtune_pk [V] * Kvco[Hz/V];
Jitter [s] =  {(Fvco_pk -  Fvco_av)/Fvco_av } * Tvco_av [s]

Is the above correct estimation of ring pll jitter?

Thank you