Попробуйте это:
FL.POP = read.csv("C:\\Users\\jevans\\Desktop\\Jessica School\\Florida population 2010-2019.csv", header = TRUE )
model<-lm(Population_Estimation ~ Year, data = FL.POP)
model
plot(Population_Estimation ~ Year, data=FL.POP, main = 'Florida Population')
abline(reg = model, col='red')
newdata<- data.frame(Year = c(2019,2020,2021,2022,2023,2024,2025))
pred <- predict(model, newdata = newdata)
newdata$Population_Estimation <- pred
FL.POP <- rbind(FL.POP, newdata)
Если вы хотите перезаписать файл CSV вместе с прогнозами,
write.csv(FL.POP, "C:\\Users\\jevans\\Desktop\\Jessica School\\Florida population 2010-2019.csv")