It is a common misconception among applicant's that they need to evidence the Cash Savings of GBP 62500 at the time of filing of the Indefinite Leave to remain ( ILR ) under the 5 year route to Settlement.
Please note that the Cash Savings of GBP 62500 is only required to be met at the time of the Entry Clearance / Initial leave to remain and again at the Extension / further leave stage under the 5 year route to Settlement.
At the ILR stage, the savings requirement would be GBP 34600, if the financial requirement is to be met only by Cash Savings, this is calculated by adding the financial requirement of GBP 18600 to the base amount of GBP 16000. If you have any dependants applying with you, then the you will have to add the financial requirement amount to the the base amount of GBP 16000.
if applying with one dependant - GBP 22400 plus GBP 16000 = GBP 38400
if applying with two dependants - GBP 24800 plus GBP 16000 = GBP 40800
and so on..