Trends in fiber properties of the U.S. Cotton crop are impacted by numerous factors, including both the varieties planted and environmental stresses encountered each year. In this paper, two statistical methods were utilized to determine the impact of year and variety on fiber quality parameters: trend line analysis and partitioning the variation from different sources by analysis of variance. The analysis of variance approach determined that the contribution of year to year variation to staple length and micronaire was greater than the variation due to variety planted. Fiber strength was much more dependent on the variety planted, than on yearly variation. The trend line analysis of USDA-Smith Doxey data from 1994 to 2000 had a very similar trend line to a single variety, NuCOTN 33 B, for micronaire and fiber strength, indicating that the year to year variation is a stronger source of variation than variety. The exception to the trend line analysis is with staple length, where the USDA-Smith Doxey summary has a negative slope over the past 7 years, while NuCOTN 33 B has a positive slope. Two example states were used to assess changes in varieties planted over the past 6 years. The number of varieties planted in GA has more than doubled between 1995 and 2000, while the number of varieties planted in MS has remained relatively constant at near 12 varieties to plant 90% of the acres. The shift in variety selection from 1995 to 2000 has resulted in fewer acres in both states of varieties with staple length greater than 35 (32’s inch) planted, fewer acres of varieties with strength greater than 30 g/tex planted, and different shifts in micronaire between MS and GA: fewer acres in GA planted to varieties with 4.4 to 4.6 micronaire and MS planting more of the varieties in the same range of micronaire. These changes in the fiber quality of the varieties planted indicate that fiber quality may not be the primary variety selection factor. Varieties are likely being selected by growers based primarily on yield, maturity, and profitability.