Nivo Charts - Minimum Value

Maybe an obvious one, but does anyone know how to set the minValue on a Nivo Bar Chart?

Basically, my dataset contains a label, and a count. The lowest value in my set is 1, not zero, and so my barchart y axis starts at 1. I’d like it to start at zero. I took a look here:
Was hoping it would just be a case of putting the minValue property into the options param, but this doesnt seem to work.

Has anyone else managed to get around this one?