Fig. 7From: Accumulation of wear and tear in archival and library collections. Part II: an epidemiological studyLoading of the PCA, showing the correlations between failure, number of requests in the reading room, prior owner, age, weight and thickness of different types of bindings. The % variance explained by the principal components is in parentheses. a n = 65; b n = 42; c n = 15; d n = 38Back to article page