Table 1. Bull data summary statistics from the list of active AI Holstein dairy bulls available in the United States as of October 27, 2017.

Variable	Mean	Standard Deviation	Minimum	Maximum
Pounds of protein	849	20.36	751	910
Pounds of fat	1040	27.82	935	1115
Somatic cell count	0.61	0.17	0.01	1.00
Calving ability	95.24	22.63	0.10	150.20
Daughter pregnancy rate	9.41	1.89	3.9	16.1
Udder composition	4.22	0.85	0.01	6.55
Livability	85.50	2.19	78.90	91.60
Bull semen price	15.25	6.78	2.00	32.00