The sale order for the IPT Bull Sale will be determined by using the Power Score.
Power Score (PS). The PS will be calculated for a bull based on “Percentile Rank” for two $ Value Indexes. The 2013 PS for bull will use the following equation.
PS = (% Rank $W + % Rank $B)/2
For the breeds these include: Angus- % Rank for $W & $B; Simmental- % Rank for API and TI; Hereford- % Rank for BMI & CHBI.
PS Example. The following four Angus bulls are representative of those sold through previous IPT Bull Sales. If we are to rank these for use in a rotational system in which females will be used as replacements in the cowherd and steers fed and sold on grid market:
Bull $W $B
A 31.08 62.80
B 27.84 57.01
C 30.33 55.52
D 34.91 69.92
To calculate the PS for the bulls above, use your breed’s most current Percentile Breakdown for Non-Parent Bulls to determine percentile ranks for the various traits. The PS for these four Angus bulls based on the “Percentile Ranks from the Sire Evaluation Report – Non-Parent Bulls.”
Sire A: (20+35/2 = 55 /2 = 27.5
Sire B: (45+55)/2 = 100/2 = 50.0
Sire C: (25+60)/2 = 85/2 = 42.5
Sire D: (5+15)/2 = 20/2 = 10.0
Thus, the order of sale for the four bulls would be…
1st – Sire D = 10.0 2nd – Sire A = 27.5 3rd – Sire C = 42.5 4th – Sire B = 50.0
Obtaining Most Current Percentile Rank. A copy of the Fall 2012 Percentile Ranks from 1 to 100 for Angus, Purebred and Composite Simmental can be found on the IPT Bull Sale Web Page at …WWW.IPTBullSale.com
Breeds without index values (Red Angus) will still use the “6 trait Power Score”.