CSD conducts large scale variety trials in all the cotton growing districts each season. It is well known that variety performance often differs markedly from season to season. It is therefore desirable when choosing which varieties to grow to study results for as many seasons as possible. This has been done for a number of districts using the average variety yields from all the CSD trials conducted in various districts as a percentage of the CSIRO variety, Siokra 1-4. This variety in recent years has been included as the standard for comparison in all the trials. The Pioneer - Deltapine variety Deltapine - Acala 90 (DP90), grown in Australia for a number of years has also been included in almost all the CSD trials and its performance relative to Siokra 1-4 is also included. In some cases where a new variety has only had limited testing but is closely related to its predecessor (e.g. Sicala V-1 and Sicala V-2; and Siokra L22 and Siokra L23) results are combined ro allow a longer tenn perspective of performance