classes — a number of persons or things regarded as forming a group by reason of common attributes, characteristics, qualities, or traits; kind; sort: a class of objects used in daily living.
measures — a unit or standard of measurement: weights and measures.
orders — an authoritative direction or instruction; command; mandate.
proportions — comparative relation between things or magnitudes as to size, quantity, number, etc.; ratio.
rates — the amount of a charge or payment with reference to some basis of calculation: a high rate of interest on loans.