Paper Question

Hello: I will try and simplify this. Let's say I have 20 different press sheet papers and I am measuring the *L*a*b values of the paper in M0 mode to see if they fit under Gracol2006, SWOP3c2, etc. Is there a rule of thumb as to the allowed variance; not a DeltaE variance; but a plus/minus variance? One paper may be L: 95, a: 0, b: -2 (Gracol2006) another may be L: 92 a: 1, b: -1 (could be SWOP3v2 or Gracol2006) So; if Gracol is L: 95, a: -0.03, b: -1.95 can I look at something as simple as L: 95 +/- 2, a: -0.03 +/1, b: --1.95 +/- 1 Thanks - Mike Stewart