Many lenders will use a year to date calculation to determine you annualized monthly income. Use this calculator to estimate the monthly and annual year to date income. This web calculator is ideal for the USDA loan (or any other loan for that matter). The operation is simple enough. Enter the year to date income in the YTD box, choose the start date, then the ending date and click outside the box or click calculate button. If you desire to "add in" to the monthly and annual incomes, click on the Add to total box.