Adjust keyboard increments preference in Photoshop (as with InDesign)

I have been using Photoshop for a while now (I remember PS 3) and I've noticed something in 2015.5 and now in 2017.

My type increments in 2.17 values using the keyboard shortcuts. So if I enlarge text it goes up in 2.17 amounts. If pixels are set, or points are selected it will increase in steps of 2.17. This is for both type size and line height.

There is a preference within InDesign that you can set these values to a specific amount, is there one in Photoshop that I've missed all these years?

Have I missed something, have I adjusted a setting accidentally?

Some help would be massively appreciated as I use type in Photoshop a fair bit.

Thanks.