[seqfan] Records for cumulative prime scarcity

[Allan Wechsler]

Let f(n) = pi(n) / n
... where pi(n) is the number of primes <= n (A000720).

Setting aside the anomalous f(1) = 0, what are the values of n for which
f(n) reaches record low values?

f(2) = 1.000
f(9) = 0.444+
f(10) = 0.400
f(16) = 0.375
f(22) = 0.363+  [2,9,10,16,22 ... is already not in OEIS]
f(25) = 0.360
f(26) = 0.346+
f(27) = 0.333
f(28) = 0.321+
f(35) = 0.314+
f(36) = 0.305+

Is this an uninteresting variant or transform of something that is already
in the Encyclopedia?