This attribute contains the MER data for the active subcarriers in the instance of the DsOfdmChannel. The data represents Integer modulation error ratio measurements in 0.25 dB steps (0x00-0xFE represents 0-63.5 dB; 0xFF indicates no measurement available). These are encoded as a packed sequence of 8-bit values for N consecutive subcarriers (N less than or equal to 7680) from lowest active subcarrier to the highest active subcarrier, including all the subcarriers in between. This attribute is a variable length and is dependent on the channel width and the number of active subcarriers that are available. This attribute is a channel level measurement and is independent of the profile being tested.