How is the amount of stipulated maintenance determined if not specified?

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Imam Ahmad indicated that the partner should spend on maintenance in a manner consistent with how he would maintain himself, without transgression or damaging the capital. He did not set a fixed amount because prices fluctuate. If the parties disagree on the amount, Abu Al-Khattab suggested that for food, one should refer to the amount provided for expiation (Kaffarah), and for clothing, to the least complete garment befitting his station.