This field is optional, if you want to check the price date of the material. Enter the information in date format. Material with prices that are older than the date entered in this field, will appear under the Warning tab. This function is used to see if the calculation is based on material prices that are outdated and that have not been revised for a long time. You can compare all the price alternatives, except for Average purchase price and Latest purchase price, to the Oldest price date for purchased parts.