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hi, i calculate the log-returns in return1 and i want to get the performance for the security. with only one security i have the following code # create matrix to keep performance return100=matrix(rep(100,length(return1)+1)) # matrix for the sum z1=matrix(rep(0,length(return1)+1)) # suming up the returns from current index to start for (i in 1:length(return1)) {z1[i+1]=sum(return1[c(1:i)]) }