[vverityv]

I recently performed an experiment in which I extracted vanillyl alcohol in ethyl acetate and water

The Kd in ethyl acetate and water is known to be 1.29 and my value was 1.14.  Is there a reason why it is so low?  I know that when transferring the liquid away from the drying agent to be boiled off if any of the drying agent is transferred it will give a particularly high Kd, but I'm not really sure what to make of it if it's too low.  Loss of product from the drying agent maybe??

Also, does anyone know what a 'good' %error would be on an extraction experiment?