0.54
http://www.renoise.com/node/783
Have changed the ranges for arithmetic to correspond with the correct renoise values. Renoise 50% groove equates to 66% (rounded) Linn drum swing, officially! 
Thanks to dBlue for his tool and explaination here in post number 4:
https://forum.renoise.com/t/global-groove-documentation-how-does-it-work/41552