Except as provided in subs. (11m) and (11s), monthly payments made under s. 20.437 (2) (dz) and (md) to persons or to families with dependent children shall be based on family size and shall be at 80 percent of the total of the allowances under pars. (b) and (d) plus the following standards of assistance beginning on September 1, 1987:

Grants shall vary in 2 areas which shall be groups of counties designated by the department based on variation in shelter cost.