<prompt> Translate the following text to EnglishIkiwa wanandoa wetu wa nadharia walikuwa katika safu ya juu ya kodi ya mapato na michango yao inawakilisha akiba mpya yote, punguzo lao la 4,000 lingegharimu serikali 1,584 na kuongeza 2,416 kwa akiba ya kitaifa.  <response>: If our hypothetical couple were in the highest income tax bracket and their contributions represented all new saving, their 4,000 deduction would cost the government 1,584 and add 2,416 to national saving. 