mean | indeterminate mode | a standard deviation | indeterminate variance | indeterminate skewness | indeterminate

1/(π b ((x - a)^2/b^2 + 1))

P (X<=x) = (tan^(-1)((x - a)/b))/π + 1/2

10th | a - 3.07768 b 25th | a - 1 b 50th | a 75th | a + b 90th | a + 3.07768 b