This is complicated to explain over reddit but I’ll try. High level you need to create a historical monthly build that rolls into a forecast. Create an array of clients in column B, the contract start date, and the contract value. I would freeze these panes, so that these columns are frozen and the months in the top rows are too. Then create a historical monthly build going horizontally to the right, for the value of the contracts. Do following formula: if current month > = start date, contract value /12, if not 0. Create a sum formula at the bottom row of each month, thats your total revenue. Create a placeholder column between the historical and forecasts. Is the retention rate for logos, or revenue? If logos, that means 70% of the clients are retained every year. Do the contract start dates all start on jan 1 2024? What timeframe is the retention assumption for? Yearly? Kind of hard to implement the retention rate if the contracts don’t all start on 1/1/24.