set.seed(1115)
x = round(rnorm(10,200,15))-20*(1:10); x
 [1] 176 169 127  99  96  92  45  70  10  12
acf(x)
acf(x, plot=F)

Autocorrelations of series ‘x’, by lag

     0      1      2      3      4      5      6      7      8      9
 1.000  0.625  0.299  0.138 -0.060 -0.177 -0.304 -0.363 -0.434 -0.223