That's really useful Xinhuan, thanks. I'm playing around with 0.5^1/8 etc

assuming n=8 to simplify things for selecting targets, it gets really easy

after 1 hour, DR = 0.5^0.125 = 0.917

here is my table that I typed out in OneNote:

.5^.125=0.917 1 hour n=1/8
.5^.25=0.8409 2 hours n=2/8
.5^.375=0.7711
.5^.5=0.7071
.5^.625=0.6484
.5^.75=0.5946
.5^.875=0.5453
.5^1=0.5 8 hours n=1

Then we just add all the DR's up for multiple hits.