enzymatic inhibition protocol - (Oct/23/2010 )

Hello everybody!
I need some help to understand an activity assay protocol.
This protocol says that to measure the proteolytic activity of SAP from C. albicans 0.02% of resorufin-labeled casein is used? What does O.02% mean?How is this concentration expressed?

thanks!!!!

I’d assume weight/weight (approximately weight/volume).
100% = 1g/mL
0.02% = 0.2mg/mL