Kapil is self$-$employed and prepares a single spreadsheet setting down his business expenditure each year. He typically records $2,000-3,000$ different individual receipts each year for different amounts, categorised as travel and subsistence, administration, motor expenses, sales and marketing and energy bills. The spreadsheet is only used by Kapil and is only kept as a historical record to give to his tax accountant.

Which of the following functions will make the spreadsheet easier for Kapil to work with and help minimise the risk of him miss$-$posting or making other errors?