set.seed(224)
e = rnorm(100, 0, 15);  x = rnorm(100, 100, 15);  y = x + e
r.obs = cor(x, y);  r.obs
## 0.6996899
plot(x,y, pch=20)

set.seed(218)
B = 10000;  f.re = numeric(B)
for(i in 1:B) {
  ix = sample(1:100, 100, rep=T)
  r.re = cor(x[ix],y[ix])
  f.re[i] = r.re/r.obs }
L.re = quantile(f.re, .025);  U.re = quantile(f.re, .975)
r.obs/U.re; r.obs/L.re
    97.5%
0.6200286
     2.5%
0.8262627