A superabundant number is an integer n that sets a new upper bound for its ratio with the divisor sum function σ. In other words, n is superabundant if and only if, for all positive integers x that are less than n:
$$\frac{\sigma(n)}n>\frac{\sigma(x)}x$$
For a few of the values:
n σ(n) σ(n)/n superabundant
1 1 1.0000 yes
2 3 1.5000 yes
3 4 1.3333 no
4 7 1.7500 yes
5 6 1.2000 no
6 12 2.0000 yes
7 8 1.1429 no
8 15 1.8750 no
9 13 1.4444 no
A longer list of these (for test cases) can be found at OEIS A004394.
One highly recommended negative test case (if your interpreter can handle it) is 360360, because it ties with the last superabundant number.
Challenge
Your program should take in a single positive integer, and output a truthy or falsey value representing whether that integer is superabundant.
As this is code-golf, the shortest answer in bytes wins.