if (!require(fmsb)) { install.packages("fmsb"); library(fmsb) } Years <- 1950+0:13*5 TFRs <- Jvital$TFR[Jvital$YEAR %in% Years] # Extract TFRs in census years CWRs <- numeric(length(Years)) for (i in 1:length(Years)) { Child <- sum(Jpop[1:5, sprintf("M%d", Years[i])]+Jpop[1:5, sprintf("F%d", Years[i])]) Woman <- sum(Jpop[16:45, sprintf("F%d", Years[i])]) # Assume repro ages as 15-44 yrs. CWRs[i] <- Child / Woman } plot(CWRs, TFRs, pch=16, type="b") text(CWRs, TFRs, Years, pos=3)