8. a. The weighted enrollment for each school district and county vocational school district shall be calculated as follows:
WENR = (PW x PENR) + (EW x EENR) + (MW x MENR) + (HW x HENR)
where
PW is the applicable weight for kindergarten enrollment;
EW is the weight for elementary enrollment;
MW is the weight for middle school enrollment;
HW is the weight for high school enrollment;
PENR is the resident enrollment for kindergarten;
EENR is the resident enrollment for grades 1 - 5;
MENR is the resident enrollment for grades 6 - 8; and
HENR is the resident enrollment for grades 9 - 12.
For the purposes of this section, ungraded pupils shall be counted in their age-equivalent grade.
b. The base cost for each school district shall be calculated as follows:
BC = BPA x WENR; and
the base cost for each county vocational school district shall be calculated as follows:
BC = BPA x WENR x 1.31
where
BPA is the base per pupil amount; and
WENR is the weighted enrollment of the school district or county vocational school district.