Based on the chart at PiersDiesel.com, I'm going to extrapolate that it would be roughly 6. 7 mm. It seems pretty linear from 11. 5 to 16 degrees such that for each 1/2 degree of timing the lift increases by . 1mm. If that holds, 16 degrees to 21 degrees is 10 half-degree changes. Add 1 mm (10 times . 1mm) to 5. 6mm at 16 degrees and you get about 6. 6 or 6. 7 mm lift at 21 degrees.
Should be close.
-Jay