Table 2. Pig carcass weight and backfat thickness according to the Grading System for Pig Products in Korea

	Grade 1+	Grade 1	Grade 2	p-value1)
Carcass weight (kg)	87.6 ± 2.64c	87.9 ± 5.27a	87.7 ± 8.98b	0.000
Backfat thickness (mm)	21.2 ± 2.06c	27.8 ± 3.90a	23.2 ± 7.33b	0.000

Each value is presented as mean ± SD.
Population numbers for Grades 1⁺, 1, and 2 are 145,872, 157,833, and 115,616, respectively.
p-value is obtained by t-test of heteroscedasticity variance.
Different superscripts in the same row differ significantly in the analysis of heteroscedasticity variance.