A system may include reception, from a planning application, of a spreadsheet including a plurality of values, presentation of the plurality of values, reception of a first instruction to change a first value of the plurality of values to a second value, presentation, in response to the instruction, of a visual indication in association with the second value, the visual indication indicating that the second value is a fixed value, reception of a second instruction to refresh the spreadsheet, and in response to the second instruction, determination of one or more of the plurality of values of the spreadsheet, each of the determined one or more of the plurality of values presented in association with a visual indication indicating that the value is a fixed value, and transmission of the determined one or more of the plurality of values and a request to refresh the spreadsheet to the planning application.