Land Rental

Hi,

I would like to ask on how to achieve computation of payment for land rentals. Let us say that we have a contract with the land owner to rent his land, the rate is 50,000 per year now after 5 years the rate will go up to 60,000 per year then every after 2 years the rate will keep increasing by 1500. How will this forecasting be possible in SAP? Is this possible via fixed asset or is there any other way?

Thanks,

Emil