<prompt> Translate the following text to SwahiliCity carrier time is derived from the USPS Cost Segments and Components Report for FY 1999 and the average time is  <response>: Wakati wa usafirishaji wa mji ni kutoka kwa Ripoti ya Sehemu za Gharama na Vipengele vya USPS kwa FY 1999 na wastani wa muda ni 