Anorexia in males accounted for approximately six percent of cases seen in an eating disorder clinic.
Anorexia in males accounted for 1/2 of all cases.
It accounted for only 6%, not 50%. It's difficult because the system doesn't seem to understand what 1/2 translates to in percentage.
( z1 account :ARG0 ( z2 anorexia :location ( z3 male ) ) :ARG1 ( z4 case :ARG1-of ( z5 include :ARG3 "1/2" :ARG2 ( z6 case :mod ( z7 all ) ) ) ) )