benchmarking Fibo/Iterate
time                 4.492 μs   (4.445 μs .. 4.544 μs)
                     0.999 R²   (0.998 R² .. 0.999 R²)
mean                 4.514 μs   (4.470 μs .. 4.572 μs)
std dev              168.7 ns   (124.7 ns .. 228.8 ns)