Where has the 'Precision' option gone for the measuring tool? Adobe Acrobat Pro DC

I have had to rebuild my computer after a catastrophic crash.  Having reinstalled Adobe Acrobat Pro DC the 'Precision' element of the 'Scale Ratio and Precision' options for the measuring tool has disappeared.  Where do I find it now?  I assess a lot of drawing plans and the 2 decimal places are not helpful (and get in the way) 

(I have read up from other's posts that you can run Java scripts etc to alter all the dimensions in one go, and I am also aware that you can overrite the dimensions using the comments panel - but both of these are time consuming or too technical for lil'ole me, and I'd just like to get back to the simple process of choosing precision).  

Can anyone help me please?