R version 2.9.0 (2009-04-17)
Copyright (C) 2009 The R Foundation for Statistical Computing
ISBN 3-900051-07-0

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> y <- c(4.969,3.830,748,390,1.295,1.075,219,7.045,5.586,1.459,1.599,538,168,230,135,107,421,1.200,321,n.m.,641,147,5.078,2.221,1.989,167,700,2.769,1.096,1.103,355,214,5.079,542,85,1.450,710,1.560,502,230)
Error: object 'n.m.' not found
Execution halted