Adjusting texture placement in material tag

#1

I’m adjusting the size of a texture on a model using the material tag, using the offset and length options. Is there a way to lock the length U and length V and scale the texture of both together?

#2

I have discovered if I shift click on both Length U and Length V, then change one of the values, then hold command + shift and hit enter, the other value changes proportionately.