rises pose a risk to the ability to cover minimum subsistence needs, the legislature may not wait until the next regular update of standard need levels. b) The legislature must ensure that the minimum level of mobility needs necessary for existence can actually be covered (see C II 2 e cc above). 145 c) The legislature must refine the distribution schedule if significant changes become apparent […] that clearly render unrealistic the allocation of consumer expenditure in family households […] using the distribution schedule hitherto in use (see C II 2 g cc 2 above). 146 d) The legislature must ensure that the model it chooses permits that any underfunding, arising because of the statistically determined monthly lump sum modified by subsequent reductions, be covered by internal compensation or by putting aside savings (see C II 2 f bb 2 above). It is within the legislature’s leeway to create sufficiently large financial leeway for such measures, or to provide for an independent benefit claim for a grant in addition to standard benefits for existential needs that can clearly not be covered from the lump sum, or, where public services are involved, to provide relief from or deferment of such costs. 147 2. Benefits provided in the form of vouchers must be usable without incurring extra expense. The newly-created statutory arrangements must be interpreted as a legal claim with regard to the reimbursement of travel expenses […] (see C II 2 g cc 3 b above). 148 III. Beyond the provisions expressly challenged here, the decision concerning the determination and level of benefits to cover standard needs also affects their later versions and successor provisions (cf. BVerfGE 125, 175 <256 and 257>). Kirchhof Gaier Eichberger Schluckebier Masing Paulus Baer Britz 28/29 149