Your club should agree on what method you want to use and it should be consistent. The IRS allows a lot of flexibility for partnership allocations but does require that they be agreed to by all the partners and that they have "Substantial economic effect". That means they are based on business requirements, not just to try and reduce taxes. If the method is not defined, it must be made in accordance with the "Partners interest in the partnership" In a club, this can change every time member payments are recorded which is why time based is the default allocation method.