Formula used
The calculator uses the formula implemented in this page's JavaScript, based on the fields shown in the tool and the result breakdown displayed after calculation.
The visible result breakdown is part of the formula disclosure. If a page has calculator-specific intermediate values, they are shown after you select Calculate.
Worked example
Example inputs: Use the default values shown in the calculator form, then adjust one input at a time to compare scenarios..
Run those values in the calculator, then change one field at a time to see how the result responds.
Editorial and correction notes
This page is maintained by the swervice editorial workflow. Formula changes should be checked against the on-page implementation and, where relevant, a primary source or documented standard.
To report a calculation issue, send the page URL, inputs used, expected result, and supporting source through the contact page.