Mixed-model methods were used to evaluate 52 Holstein sires in artificial insemination for milk, fat, and protein yield and fat and protein percent. A total of 3288 305-day first lactations of Holstein on the Dairy Herd Analysis Service were studied. Sires were grouped by year of first service, and groups were used to measure trends in the average generic merit of sires sampled. Annual genetic trends among sires were 85, 1.4, and 1.0kg for milk, fat, and protein yield and kg for milk, fat, and protein yield and −.029 and −.031% for fat and protein test. Genetic trends among their daughters were estimated for Quebec herds according to relative sire usage. Trends in yields were positive. Average yearly genetic gains for milk, fat, and protein yield were 46, 1.1 and .5kg for all herds and 57, 1.9, and 1.1kg for herds in Analysis Service. Trends for milk composition were negative. Annual genetic declines in fat and protein percent were −.004 and −.008% for the population and −.003 and −.014% for herds in Analysis Service.