Figure 8From: Evaluation of gene expression data generated from expired Affymetrix GeneChip® microarrays using MAQC reference RNA samplesPercentage of Present calls based on 8,550 common genes There is a significant difference in the percentage of Present calls between unexpired U133Plus2 microarrays (73.6%) and expired U133A microarrays (64.5%). Based on microarray data generated in 2009.Back to article page