<prompt> Translate the following text to SwahiliThey sponsored evidence challenging the need for a cushion so substantially above and beyond the Postal Services own best estimate of future increases in the cost of collecting, processing and delivering the mail.  <response>: Waliunga mkono ushahidi unaopinga haja ya kuficha kwa kiasi kikubwa zaidi ya makadirio bora ya Huduma ya Posta ya ongezeko la baadaye la gharama ya kukusanya, kusindika na kupeleka barua. 