<prompt> Translate the following text to EnglishWakati bei ya hisa ilipopungua kwa robo katika siku moja mnamo 1987, uchumi wa Marekani haukuona, shukrani kwa hatua ya haraka ya Hifadhi ya Shirikisho ya Greenspan.  <response>: When stock prices fell by a quarter in one day in 1987, the American economy barely noticed, thanks largely to quick action by Greenspans Federal Reserve. 