For instance, for identifying a program characteristic such as age or gender, identities such as 00 (teenagers) 01 (twenties and thirties), 10 (forties and fifties), or 11 (sixties) may be indicated in a lower 2 bit portion of the Rfa field 403, and 0 (male) or 1 (female) may be indicated as a single bit of the Rfa field 403.