Meeting the financial requirement FLR

Hello everyone
Need some help please

We should apply for FLR in April for my wife .
* I am working on the same company from 2017 my monthly wage £1560 (x12)= 18720 gross
* On HM revenue tax letter My taxable income £18532.80
And will be less than 18600 on my next p60
Because of the smart pension deduction
Does the home office consider the annual salary before the pension deduction or after the pension deduction.

Thanks

Anyone please