Comparing Investments This calculator compares the net gain of a taxable investment versus a tax-favored one. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Have A Question About This Topic? Name Email Address Message Thank you! Oops! Related Content Is a SEP-IRA Right for Your Business? For some, the idea of establishing a retirement strategy evokes worries about complicated reporting and administration. 18 Years’ Worth of Days The average retirement lasts for 18 years, with many lasting even longer. Will you fill your post-retirement days with purpose? Problems with Probate Probate can be a completely public process, or it can be managed to include as little information as possible.