FM to Delete dollar '$' sign

Hi experts,

I want to write a FM to check the amount value (data type KF/currency) if there is any $ sign before the amount. Say $15400.00, I would like to remove the $ sign from 15400.00. If it is -$145.00, delete dollar symbol and keep -145.00.

I have thousands of custom KF and have to implement it in BW. So I want this FM to call it from Transfer Rules start routine and will check one by one field only if it is a KF and remove $ sign if there are any. Please help.

Any help will be appretiated with points.