R spread value evenly over years

I have a list of values that I want to spread evenly over multiple years in R. I think I’m missing something right in front of me.

I have:

#Create dataframe
df <- data.frame(product=rep(c('A','B')),
                 QTY = c('45', '90'))

#Check
df

# List Years
years <- c(2022:2027)

I would like to spread the values of each product evenly over the years listed ending with something like

>Solution :

Perhaps this helps – divide the ‘QTY’ by the length of ‘years’ (+ 1) and use crossing to expand the data

library(dplyr)
library(tidyr)
df %>%
    mutate(QTY = as.numeric(QTY)/(length(years)+1)) %>%
    crossing(Year = years)

-output

# A tibble: 12 × 3
   product   QTY  Year
   <chr>   <dbl> <int>
 1 A        6.43  2022
 2 A        6.43  2023
 3 A        6.43  2024
 4 A        6.43  2025
 5 A        6.43  2026
 6 A        6.43  2027
 7 B       12.9   2022
 8 B       12.9   2023
 9 B       12.9   2024
10 B       12.9   2025
11 B       12.9   2026
12 B       12.9   2027