Table:
undergraduate degree
graduate degree

unadjusted gap
adjusted gap
unadjusted gap
adjusted gap

model a
model b
model a
model b

percent

cohort

2006
-1.9
-1.8
-0.6
-5.8
-3.7
1.7

2007
-0.5
0.6
0.7
-15.8
-13.1
-8.2

2008
..
..
..
..
..
..

2009
-7.6
-7.3
-7.8
-9.8
-8.1
-9.4

2010
-7.7
-7.2
-10.0
-13.6
-9.8
-8.4

2011
-10.1
-8.5
-11.1
-3.2
2.1
0.5

Statement: even after taking demographic and field of study differences into account, undergraduate students who graduated in 2009 earned 8% less than those who graduated in 2008.
Question: even after taking demographic and field of study differences into account, how many percent of undergraduate students who graduated in 2009 earned is less than those who graduated in 2008?
Answer: [8.1]