In a method for parsing data in a data unit into a number of spatial streams, a modulation and coding scheme (MCS) is selected from a plurality of MCSs. Information bits are encoded using one or more encoders to generate coded bits, wherein the number of encoders used depends on the selected MCS. The coded bits into a number of spatial streams according to a first set of parsing rules if the coded bits satisfy a parsing constraint. The coded bits are parsed into the number of spatial streams according to a second set of parsing rules if the coded bits do not satisfy the parsing constraint.