Contract Rate vs. Permanent Salary (Sydney)

I did some research on comparing Contract Rate with Permanent Salary.

Formula:
CA = PS/2
CB = 12CA/11*0.91) (1months holiday/leave, 9% super)
CR1 = 12CB/11 (1month period for job seeking)
CR2 = 6CB/5 (2months period for job seeking)

Abbreviations:
PS = Permanent Salary
CA = Contract Rate
CB = Contract Rate (considering holiday/leave/super)
CR1 = Contract Rate (considering holiday/leave/super + 1 month job seeking)
CR2 = Contract Rate (considering holiday/leave/super + 2 months job seeking)

PS CA CB CR1 CR2
80k 40 47.95 52.31 57.54
100k 50 59.94 65.39 71.93
120k 60 71.93 78.47 86.32