It Was the Best of Times, It Was the Worst of Times All about how missing the best market days (or the worst!) might affect your portfolio. Share | Related Content Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates. Defining Your Priorities Achieving a long-term goal, like retirement, starts by taking small actions today. 401(k) Plans Are Not Just for Big Businesses Many small businesses are one person businesses.