In apportioning the county into commissioner districts, the county apportionment commission shall be governed by the following guidelines in the stated order of importance:

    (a) All districts shall be single-member districts and as nearly of equal population as is practicable. The latest official published figures of the United States official census shall be used in this determination, except that in cases requiring division of official census units to meet the population standard, an actual population count may be used to make such division. Other governmental census figures of total population may be used if taken subsequent to the last decennial United States census and the United States census figures are not adequate for the purposes of this act. The secretary of state shall furnish the latest official published figures to the county apportionment commissions forthwith upon this act taking effect, and within 15 days after publication of subsequent United States official census figures.

     A contract may be entered into with the United States census bureau to make any special census if the latest United States decennial census figures are not adequate.

    (b) All districts shall be contiguous.

    (c) All districts shall be as compact and of as nearly square shape as is practicable, depending on the geography of the county area involved.

    (d) No township or part thereof shall be combined with any city or part thereof for a single district, unless such combination is needed to meet the population standard.

    (e) Townships, villages and cities shall be divided only if necessary to meet the population standard.

    (f) Precincts shall be divided only if necessary to meet the population standard.

    (g) Residents of state institutions who cannot by law register in the county as electors shall be excluded from any consideration of representation.

    (h) Districts shall not be drawn to effect partisan political advantage.